This Week's Horticulture News/Information

Looking Ahead: Plan to Help Pollinators Next Year

Kicking back to consider next year’s garden, let benefitting pollinators be one of your considerations.  Of course pollination is important to us because we like to eat—one-third of our food supply exists because pollinators pollinate.  Pollinators, specifically native bees, are real work horses of the pollination world—just 250 native bees do the work of thousands of honey bees.

Some native bees, like the bumble bee, colonize, meaning they hang out together in a social structure with everybody having a specific job to do.  The vast majority of native bees, however, are solitary, living out their lives with no honey to make or designated job to complete.  Why is this important, you ask?  Because improving the environment of a solitary bee involves different strategies than those for hive bees where intervening efforts are concentrated. This doesn’t mean there’s nothing to do to help native bees, quite the contrary.

Plant native flowering plants.  Not only are these plants tough for a reason, the flowers provide a protein source—pollen—and a sugar source—nectar—for developing larvae and adults. Because it’s important to have food sources available in spring, summer and fall, select plants for the time they are in flower.  Group same plants together to better attract pollinators.

Choose to leave a few weeds.  Clover and dandelions are excellent food sources for pollinators. This doesn’t mean the entire yard has to be covered in weeds but a pollinator-friendly yard can be strategic by leaving some weeds in designated areas.

Rocks and pebbles are important in a watering dish. Pollinators will drink from bird baths but be sure to prevent them from drowning by placing rocks and pebbles for insects to alight while getting water. Change out the water every other day to keep mosquito populations down.

Put in a pollinator hotel. This provides cavity-nesting native bees with a place to lay eggs and provision their young with a pollen-nectar combination. Different diameter holes, along with specific depths of holes, will attract different bees.  Find out how to build a pollinator hotel with this NebGuide:  http://extensionpublications.unl.edu/assets/pdf/g2256.pdf .

Use pesticides—herbicides, insecticides and fungicides—sparingly or not at all.  These products have the capability of killing pollinators or, for those that survive, causing erratic behavior, such as disorientation, failure to mate, and not eating.

Apply to have your garden certified as pollinator habitat through the Nebraska Pollinator Habitat program: https://entomology.unl.edu/pollinator/pollinatorapp.pdf .  Remember that any size garden, small to big, benefits pollinators.

Purple Beautyberry

As flowering plants give way to autumn, it’s the fruit that many produce that add interest to our landscapes.  It’s hard to beat the berries produced by purple beautyberry, Callicarpa dichotoma. At a time of the year when fruits highlight the reds, yellows and golds of autumn, it’s nice to see the show-stopping lustrous purple-violet fruits of beautyberry.  The fruits are small, just 1/8 of an inch across, but the numerous clusters along the stem make it a standout. 

Beautyberry should not be confused with beautybush, which is an entirely different plant with a whole other set of flowering and fruiting characteristics.

Purple beautyberry is a shrub, reaching just 36 inches or so in height.  The plant is wider than it is tall, easily spreading to 42 inches across. In our climate, beautyberry acts more like a sub-shrub, meaning the crown and larger branches survive the winter but the twigs and smaller branches do not.  No worries! Even if your beautyberry does not have any winter dieback, cutting back stems to 8 inches in the spring gives rise to more of the small pink flowers (and hence more purple-violet fruits). This hard pruning also results in more compact, less rangy plants.

Sources list purple beautyberry as hardy to USDA Zones 5-8, but I’ve been growing it in my Zone 4 garden for years now and it keeps looking better every year.  The literature lists best fruit production when two or more are planted, providing pollen for one another. This is also debatable, since my lone shrub produces LOTS of fruits every year. The fruit show lasts September through October and provides food for many songbirds.

Plant purple beautyberry in a loamy soil with good drainage. A location that receives 3-6 hours of sunlight daily means that beautyberry can be planted in those challenging locations that don’t receive direct sunlight all day.  Water during dry spells as the plant will drop fruits during prolonged dry weather. Purple beautyberry’s smaller form makes it a great addition to perennial gardens and front entrance plantings.

Give purple beautyberry a try for its showy display of fall fruits.

Growing Garlic

If you’ve grown garlic before, you know that the cloves for planting are found readily in the spring.  What many do not know is that fall planted garlic produces larger cloves than spring-planted ones.  Using this opportunity to plant now means it’s not too late to reap the benefits of fall-planted garlic.

In selecting a site to grow garlic, choose one that gets 6 or more hours of direct uninterrupted sunlight daily and has a well-draining soil.  In dense soils, garlic can rot, so amending the soil with compost first ensures a good crop. Garlic needs a nutrient-rich soil, so sandy soils will also benefit from the addition of compost.

In selecting a garlic variety, be aware there are hardneck and softneck types. Hardneck varieties store best over the winter months while the softneck types, favored for braiding together, have a short shelf life.  Garlic from the grocery store has been treated to inhibit sprouting, so it isn’t a good choice for planting. For the upper Midwest, choose hardneck varieties for their hardiness. Flavors range from mild to buttery to fiery.  There are heirloom types, such as ‘German Red’ and ‘Georgian Fire’, as well as newer types, like ‘Korean Red Hardneck’ and ‘Great Lakes’.  Whatever variety you choose, growing your own garlic is easy and opens up a world of culinary possibilities.

Each garlic clove produces one head of garlic.  The larger the clove planted, the larger the head of garlic produced.  Separate the cloves from the bulb when you’re ready to plant.  The flat basal plate goes to the bottom of the hole, with the point facing skyward.  Holes should be 3-4 inches deep and spaced about 6 inches apart. The first thing the clove does is put down roots to maintain moisture levels.  In some instances, there may be green growth sprouting from cloves but this greenery should not be cut off, instead leaving it to nourish plants. 

In the spring, growth in earnest begins, sometimes with the plant sending up a seed stalk. The seed stalk should be snapped off to encourage the plant to put energy into growing a larger head of garlic.  The seed stalk is edible if harvested when tender, so don’t be afraid to use it in dishes where a garlic flavor is desired. Garlic does best when plants receive about 1 inch of water per week. Bulbs are ready to harvest when the foliage dies back by about one-half.  The biggest garlic bulb can be saved back for planting garlic cloves in the fall, starting the process again.

Now that you know fall-planted garlic is easy to grow and yields great results, the next thing to do is to get out those gardening gloves!

The Brown Marmorated Stink Bug

The brown marmorated stink bug is a nuisance as well as a destructive pest and, like its name implies, puts off a nasty odor when crushed. This nonnative invasive pest has been in Nebraska since 2012. The damage the BMSB causes is from its needle-like mouthpart that punctures, resulting in sunken bruised areas on fruits. It feeds on a wide range of crops, including soybeans, corn, apple, pear, peach, cherry, peppers, tomato, maple, redbud and serviceberry, to name a few.

The BMSB is characterized by bands of white on dark antennae and white inverted V-shapes along the edge of their body. The insect itself is shaped like a shield and is about ½ inch long.

Like the Asian ladybug, the BMSB seeks winter shelter beneath house siding and structures that have openings that allow access. Once in walls, they can easily make their way inside the house where they become a nuisance, especially when their population numbers are high. Fortunately, they do not bite or spread diseases to humans, although in rare occasions their odor can cause an allergic reaction. 

BMSB can be hard to manage, in particular as they seek overwintering sites.  Spraying the foundation and siding with a home perimeter spray helps to keep the insect from gaining access inside.  Indoors, utilize a shop vacuum, putting 1-2 inches of soapy water into the tank so that bugs drown.  You can use a regular vacuum cleaner to clean up BMSB but be aware that their odor may transfer to the machine itself. Insecticides and foggers are not recommended to manage BMSB populations indoors. Check around windows, doors, chimneys and air conditioners for a tight fit and use silicone caulk and weather-stripping to close gaps.

To find out more about the brown marmorated stink bug and the crops it can damage, go to: http://www.stopbmsb.org/managing-bmsb/ .

Weed Musings

In the midst of September, if weed management isn’t on your autumn to-do list, it definitely should be. Fall is the best time to be applying herbicides to perennial weeds. Why is this so? As plants ready for winter, sugars produced in leaves are transported to the roots for storage.  With herbicide applications, the plant’s internal transport allows herbicides to move readily from leaves to roots, providing for excellent distribution and better control.

Recognizing something as a weed is not enough. Identification is critical to making sure your time, labor and resources are used to good effect. Crabgrass and foxtail, the bane of many lawns and gardens, are annual plants and will die with the first hard freeze. So using herbicides on annual plants in the fall doesn’t make a lot of sense.  Dandelion, ground ivy, brome grass, and poison ivy, however, are perennial plants and management efforts will be more effective now.  Plan to get at least two applications of the herbicide down before the first hard freeze, spacing the timing of the applications according to the label directions.  If you need help with identifying the weeds in your garden and landscape, the Nebraska Department of Agriculture has an excellent reference, Weeds of the Great Plains.  Information for purchase of this book may be found here: https://nda.nebraska.gov/forms/nw11.pdf .

It’s surprising how the presence of the word “weed” in a plant name brings others to the conclusion that the plant should be removed... immediately.  So if you have Joe Pye weed, butterfly milkweed, or ironweed, this doesn’t mean you should reach for the herbicide.  These are beautiful plants in their own right and benefit pollinators to boot.  While a pristine lawn may be considered the ideal, gardeners can choose to leave some weeds in out-of-the-way places to provide food for pollinators.

Sometimes the word “weed” in a plant name is justifiable, like ragweed, which causes a lot of problems for allergy sufferers. Clients once inquired about the “interesting” plant that appeared on their property.  The plant was none other than giant ragweed and the clients thought the ragweed’s growth rate was so amazing they decided to keep it!  This proves once again that beauty is ultimately in the eye of the beholder.

The Benefits of Fall Planting

The first and most important thing to know is that Fall IS for planting!  Warm soils, cooler temperatures and less weed pressure make it a perfect time to plant regardless if you’re planting trees, shrubs, perennials or Kentucky bluegrass. 

I’m often asked if this is really true. After all, isn’t the best time to plant trees, shrubs, perennials and Kentucky bluegrass is in the spring? Actually no, Fall is better.  Summer’s lingering warm soils coupled with cooler ambient temperatures are perfect, allowing plants to keep needed moisture and establish roots at the same time.  Good roots are important to winter survival and good root growth is achieved before the soil freezes in late November.

Weed seed germination is far greater in the Spring than in the Fall, so doing less cultivating to keep the weeds down means less competition for the desired plants and less work for you.

Finally, don’t miss out on the terrific sales.  If you have a bare spot in your landscape, there’s no need to wait.  Local garden centers have some wonderful sales and promotions going on, often at a significant savings compared to their Spring prices.

http://byf.unl.edu/september-garden-activities

Mosaic Virus on Squash

Viruses represent some of the toughest diseases to manage in cucumber, squash, pumpkin, and melon plants.  Often the disease doesn’t kill but does reduce the size and number of leaves, which in turn decreases fruit production. Cucumber mosaic, cucumber green mottle mosaic, watermelon mosaic, zucchini yellow mosaic, and squash mosaic are some of the viruses that infect plants in the Cucurbit family. The viruses are spread from infected seeds, by aphid feeding, and by mechanical means, such as using a gardening tool on an infected plant and then using the same unclean tool on a healthy one.

When gardeners notice mottled leaves, raised dark green blisters on fruits, and stems that dry out rapidly, a mosaic virus is the likely cause. There is no product to spray that will eradicate the virus from plants. Instead, use certified virus-free seeds, choose varieties that are resistant to mosaic, clean gardening tools with a 10% bleach solution between uses, and remove weeds from inside and outside the garden to reduce the amount of pathogen spread by insects. If you don’t already, clean up the garden this fall to remove vines that can harbor the virus.

Are squash and melons affected by mosaic virus safe to eat?  “Yes,” says Nebraska Food Safety Educator Carol Larvick, citing information from Minnesota Extension. “These viruses are specific to plants and do not harm humans. The presence of mosaic won’t cause fruits to rot prematurely but severely distorted fruit will have a different texture, so use your own judgement.”

 For more information on mosaic virus, check out this website: https://blog-yard-garden-news.extension.umn.edu/2018/09/can-i-eat-that-strange-looking-squash.html .

Landscape Journaling

Landscape journaling, the art and science of keeping track of plants and gardens in the landscape, may seem like a fluffy idea, but the task has merit. Are you having your ash trees treated every other year to prevent an infestation of emerald ash borer? A landscape journal can be a record of when and who treated the tree, along with the timing for the next treatment. Did a new pepper variety perform extremely well in your vegetable garden this year? This can be recorded in a landscape journal to serve as a reminder for next year.

More than once I’ve witnessed a tree service using lag bolts to stabilize a tree split. Successive years of ring growth over the lag bolts made them invisible to those unaware of past repairs. A concern here is that years later someone using a chain saw will encounter this metal—with scary consequences. Not only is a landscape journal an interesting bit of reading to look back on past  tree repairs, I would go so far as to say it should be included with the abstract of the property as a history of what has been done and to prevent injury to others unknowing of past tree work.

Since staking materials should be left on newly planted trees for one year and one year only, a landscape journal is a good place to record when those materials need to be removed next year. Re-training the central leader in your spruce tree after the top died out?  Put this down in the landscape journal as a reminder to remove the staking materials after one year and to track progress as the tree recovers.

Keeping a landscape journal helps us to track what happens when. I can’t tell you the number of times a tree owner will bring in a sample for diagnosis, claiming “It just happened!” when it is apparent the problem has been ongoing for years. With a set of eyes looking at plants, monitoring for problems and recording what is seen, problems are discovered—and treated—sooner rather than later.

A landscape journal can be a place to keep your plant wish list, to serve as a reminder of a monumental failure, to log vegetable crop rotations, and to stash pictures of landscapes you’d like to emulate. Weather events, a large factor in plant stress, can be recorded in a journal, providing that “ah hah” moment, connecting a cause with an effect, sometimes several years later.

Regardless if your garden journal is a hard copy or an electronic record, the information contained within will be invaluable.

 

Helen’s Flower

Helen’s flower, Helenium autumnale, is a native perennial of the sunflower family, producing show-stopping 2-inch flowers in colors of yellow, gold, orange, red or variations in between.  The notched petals, surrounding a yellowish brown globular cone, are a nice touch, giving the flowers the appearance of a ruffled skirt. The specific epithet “autumnale” refers to Helen’s flower blooms in late summer/early autumn, a perfect time when pollinator populations are really booming. Helen’s flower is also known by the unflattering moniker of “sneezeweed” which harkens back to when flower petals and leaves were dried for snuff.

Helen’s flower, along with its cultivars, are hardy to USDA Zones 3-9.  Helen’s flower is not a long-lived perennial, often lasting 4-5 years before it quietly disappears.  This trait shouldn’t sway you from growing Helen’s flower because, besides its ability to re-seed, the plant is a good food source for pollinators, displaying the greatest diversity of pollinators than any other native wildflower in University of Nebraska research.

An interesting and identifying feature of Helen’s flower is the winged stem. Thankfully, the foliage of Helen’s flower does not attract grazing from deer and rabbits. Plants are not prone to disease.

The cultivars of Helen’s flower include ‘Rotgold’ and ‘Rubinzwerg’, both readily found at garden centers and nurseries. ‘Rotgold’ has flowers of red and gold on plants three feet tall with an equal spread, making it a welcome addition to the back of the border. ‘Rubinzwerg’ is shorter, producing rusty red flowers on plants that are just two feet tall and wide.

‘Salsa’ is a new cultivar of Helen’s flower, sporting bright red flowers on plants 20 inches tall and having a similar spread. ‘Mardi Gras’ has red-orange flowers on robust 36 inch tall plants. Among the newest of the new is the Mariachi™ series, sporting bicolor flowers on 20 inch tall plants.

Although native, Helen’s flower does not appreciate dry soils, instead preferring soils that are evenly moist to downright wet, making this a good plant for rain gardens and heavy clay soils.  Helen’s flower also likes a location receiving 4 or more hours of direct sunlight daily.  In dry soil, plants will not thrive and will have a ragged appearance.  Conversely, Helen’s flower grown in a moist area will benefit from staking to hold the plant upright.

Altogether a colorful addition to the garden, consider planting Helen’s flower for the added benefit of nectar and pollen for pollinators!

 

Flowering Plants for the August Garden

When it comes to August’s garden, many gardeners, plant enthusiasts and landscapers are willing to skip the month entirely because of the seemingly few plants that provide interest during August. I’d like to challenge that notion, mainly because August is a perfectly fine month of frost-free weather and why not make good use of it? Whether your goal is to spruce up a drab corner or benefit pollinators, look to some lesser-known flowering plants to brighten your August garden.

Native plants are excellent contributors to the August garden.  The spiked gayfeather, Liatris spicata, is found in many gardens but this genus has way more to offer.  Liatris microcephala, tiny-headed liatris, packs the purple flowers onto stems just 18 inches tall. Liatris pycnostachya ‘Eureka’, button snakeroot, is a whopping 5 foot tall! Turtlehead, Chelone lyonii, is not your typical daisy-type native flower. Flowers of pink or white appear on plants adapted to shade/part shade conditions. Helen’s flower, Helenium spp., often goes by the unfair name sneezeweed because it’s not a weed and it doesn’t make one sneeze.  Cultivars range from tall to short, primarily in the red-orange-yellow area of the spectrum.

Daylilies, Hemerocallis, contribute a large number of varieties that bloom in August. ‘Challenger’ produces medium red flowers on 4 foot tall stems.  This variety was introduced into the nursery trade in 1949, proving that a plant doesn’t have to be a new introduction to be good.  Other daylilies that bloom in August include, ‘Happy Returns’, ‘Jen Melon’, ‘Jersey Spider’, ‘Mighty Chestnut’ and ‘Yuma’.

Patrinia scabiosifolia sports tiny sulfur-yellow flowers in grand clusters that make it a showy addition for August. If it’s pollinators you’re looking to attract, then plant the biennial Korean angelica, Angelica gigas. Wine-purple flowers appear on plants 2-4 feet tall. Clematis heracleifolia, tube clematis, is unlike any other clematis you’ve grown, with blue-purple tubular flowers on a 3 foot tall shrub.  Panicled hydrangea, Hydrangea paniculata, has numerous cultivars of show-stopping flowers including ‘Tardiva’ and ‘Grandiflora’.

The August garden need not be drab.  More about these plants and many others for the August garden may be found in this ISU Extension publication written by yours truly:

https://store.extension.iastate.edu/Product/Flowering-Plants-for-the-Late-Summer-Garden  .

The Extension Master Gardener horticulture helpline and open clinic hours are:

Mondays, 9:00 am to 12:00 noon, Washington County Extension, 402.426.9455

Tuesdays, 1:00 to 3:00 pm, Cuming County Extension, 402.372.6006

Wednesdays and Fridays, 9:00 am to 12:00 noon, Dodge County Extension, 402.727.2775

The Dreaded Japanese Beetle (Again)

Despite winter and spring conditions that we hoped could thwart them, the Japanese beetles are at it again. They fall on us as we mow beneath trees, eat our hard-won fruits as they multi-task, and drown in the dog’s water dish.  Here are some important considerations:

▪Japanese beetles do lay their eggs in the soil.  Managing Japanese beetle grubs to stop the damage to turfgrass IS effective. Targeting grubs IS NOT an effective means of damage prevention to trees, roses, and grape vines.  This is because there are ditches, fence lines and creek banks that are never treated for Japanese beetle grubs and emerging adults will always fly to where there is food.

▪Be aware that insecticide applications to anything with flowers on it will kill pollinators too.

▪For safety reasons, insecticide applications to food plants MUST be labeled for use on edible crops and the pre-harvest interval (PHI) followed.

▪It’s illegal to spray any systemic insecticide on trees. Systemic products are those taken in by plant tissues and distributed throughout the body of the plant.  The restricted-use insecticide chlorantraniliprole is effective against Japanese beetles but does not harm pollinators. Consider a tree service to apply chlorantraniliprole to trees as beetles emerge in June.

▪Japanese beetle feeding slows in August and plant damage decreases.  Yes trees do look lacy right now, but fortunately they do not die from Japanese beetle defoliation.

▪Japanese beetle traps are TOO good at drawing in JB. There are more Japanese beetles doing damage to plants in yards with traps than those without.

▪If collecting Japanese beetles from plants, the best time of day to do so is 7:00 in the evening. Collecting them at 7:00 results in a lower population of JB than at any other time of day. (Thank goodness for grad students who do the tedious work of collecting the data!)

▪Japanese beetles do not, I repeat do not, emit an aggregation pheromone.  An insect aggregation pheromone is an odor that is emitted to broadcast “supper at the Smith house.”  Rather, it is the plants emitting distress pheromones that draw JB to feast there.

So there you have it.  Japanese beetles are abundant, there is no one-size-fits-all remedy for managing them, and they tend to make plants look bad but not kill them. We take our lumps with gardening, along with the good.

 

Yellow Nutsedge

“What is this grass growing in my flower bed?” is a question I hear quite often now.  Rolling the stem between my fingers quickly determines this isn’t grass at all but the infamous yellow nutsedge.  Sedges are grass-like perennials that have triangular shaped stems.   If they grew at the same rate as turfgrass, many lawn owners would be OK with nutsedge growing there. Unfortunately, high heat and abundant moisture foster fast growth that easily outpaces the height of Kentucky bluegrass and fescue.   Yellow nutsedge is a particular problem in new flower beds and shrub borders if the previous space was occupied by turfgrass.  Dense lawns suppress the growth of yellow nutsedge and, once the turf is removed and landscape plants installed, yellow nutsedge can show up throughout. 

The use of “nut” in yellow nutsedge’s name comes from the small tubers, called nutlets, found at the end of roots. The presence of these nutlets helps to explain why the plant is so hard to manage at this time of the year. Removing yellow nutsedge by hand-pulling ensures nutlets will be left behind.  Once each nutlet begins to grow, where once there was one plant, now there are many. Herbicides used now will also be effective at eliminating the parent plant, but bear in mind herbicides do not translocate to the nutlets, so again, where once there was one plant, now there are many.  This isn’t to say we can’t hand-pull or use a herbicide, it just means diligence will have to be exercised to stay after new plants by repeating previous steps.

June 21 (the summer solstice) is the dividing point from when yellow nutsedge is relatively easy to manage to when it becomes a chore. Prior to June 21, plants have not reached the maturity necessary to form nutlets. Lawn herbicides containing the active ingredient Halosulfuron (Sedge Ender™, Sedge Hammer™, and Halosulfuron Pro™) applied before this date will be the most successful at managing yellow nutsedge in lawns. In gardens and borders, yellow nutsedge can be hand-pulled or spot sprayed with herbicides containing glyphosate, being mindful to shield desired plants.

From June 21 onward, the nutlets of yellow nutsedge are a tenacious survival mechanism that requires diligence (or acceptance) on our part to manage yellow nutsedge in our landscapes.

 

Caterpillars on Coneflowers

The silvery checkerspot caterpillar, Chlosyne nycteis, can be found right now, happily eating away on sunflower, aster, Echinacea, goldenrod and Rudbeckia.  The checkerspot caterpillar has branched spines on its back that are black in color. Sometimes the caterpillars will have an orange stripe or two.  Depending on weather conditions, there will be one to two generations per year. Once first generation caterpillars are an inch long, they will stop feeding and form a pupal case on foliage. As the growing season winds down, the second generation caterpillars will hibernate as third instar larvae.

The adult silvery checkerspot is a beautiful black, yellow and orange butterfly that is on the small side, with a wingspan around two inches across.  The black border on the wings will be edged with white dots. The females are more brilliantly colored than the males and males will have knobs at the end of the antennae, which helps them to find females.  This butterfly is a pollinator, feeding on flower nectar of the milkweed and red clover.

If gardeners can tolerate the loss of foliage on their plants, then by all means let the checkerspot caterpillars have at it because their population stability may be vulnerable. Caterpillar feeding tends not to destroy plants but there will be a lot of missing foliage. Where their feeding damage is a concern, grow an extra plant or two of their preferred chow and “herd” them by carefully breaking off the portion of the leaf they are on and placing it in the midst of their designated forage plant.  Harmony!

Herbicide Drift

A tomato plant sample was brought in today with curled stems and cupped leaves. Under-watering and fungal diseases were a few of guesses as to the wonky foliage while truly the blame lies with herbicide drift.  Drift occurs when desired plants receive an accidental dose of herbicide.  Depending on the herbicide, damage to vegetable plants and trees can show different symptoms--bleaching or yellowing, twisting, curling, and cupping of leaves. The most common culprits that cause curling and cupping leaves include 2,4-D (used to kill broadleaf weeds in lawns and pastures), dicamba (lawn and crop broadleaf weeds) and picloram (pasture broadleaf weeds). These herbicides are plant growth regulators, killing weeds by stimulating excessive growth and using up plant fuel, carbohydrates.

There is nothing that can be done to counter the effects of herbicide drift. Intuitively, we know there is some plant stress because distorted leaves don’t photosynthesize as well as normal ones.  Here are the most common modes of herbicide movement.

Wind

The greater the wind speed, the higher the likelihood the herbicide’s air-borne droplets will be    carried onto desired plants. Spray when wind speed is 3-7 miles per hour and set the sprayer to a larger droplet size.  Ask applicators in adjacent areas to be mindful of wind conditions and make applications when conditions are conducive for herbicides staying put.

Volatilization

A big word, a simple concept. When temperatures surpass 85° F, herbicides can vaporize and herbicide-laden vapors settle elsewhere, often where they are least desired.  If temperatures are hot, spray in the cooler morning hours.

Sprayers

Separate sprayers—one for insecticides and one for herbicides—keep herbicide residues from becoming a problem.  Mark the sprayers so you don’t forget!

Lawn Clippings, Soil, Compost and Manure

Lawns or pastures treated with herbicides can be a problem when grass clippings, soil, compost, hay, and animal manure from these sites are used in gardens and around trees. Knowing the history of how these sites are managed will help determine if these materials can be used.         

Herbicides moved via wind, volatilization and contaminated sprayers tend to be one-time incidences.  As vegetable plants and trees put out new growth, the leaves and stems will most likely be their normal shape and size, indicating plants have outgrown the effects of the herbicide.  The damage to vegetable plants via herbicide-laden lawn clippings, soil, compost, hay, and manure is ongoing, particularly if picloram was used on the lawn or pasture.  Consequently, vegetable plants don’t recover and should not be eaten.

The Extension Master Gardener horticulture helpline and open clinic hours are:

Mondays, 9:00 am to 12:00 noon, Washington County Extension, 402.426.9455

Tuesdays, 1:00 to 3:00 pm, Cuming County Extension, 402.372.6006

Wednesdays and Fridays, 9:00 am to 12:00 noon, Dodge County Extension, 402.727.2775

Mulch and Hot Weather

Mulch is an aspect of the landscape that doesn’t provoke much thought.  Wood chips or rock?  Landscaping fabric or not?  The reality is that the right kind of mulch, applied to the proper depth, has a BIG impact on plant health, especially during the heat of summer.

Root function stops when soil temperatures reach 85°F and higher.  This means no water and nutrient uptake occurs when soil temperatures are hot. No water moved through roots leads to leaf burn and heat stress. Woodchips and shredded bark act as insulation, protecting the soil from direct sunlight and buffering air temperature extremes.  The result is cooler soils that favor root uptake of water.

Mulched trees and trailing plants that are lucky enough to shade their own roots have the advantage over ones placed in rock mulches, where the absorbed heat dissipates well into the evening hours and keeps soils hotter longer.  Adding insult to injury, landscaping fabric used beneath rock interferes with root respiration (where plants roots take in needed oxygen). 

The depth of woodchip and bark mulches plays a role in plant health. A 2-4 inch layer of mulch is the right amount to keep soils cooler while allowing root access to oxygen.  Mulch piled higher than 4 inches, or mulch that extends up against the crown of trees and shrubs (the dreaded mulch volcano!) can be as detrimental to tree health as rock mulches are.  More is definitely not better!

The extent of woodchip and bark mulches also plays a role in plant health.  Devoting less real estate to lawn and more to mulching beneath tree and shrub canopies extends the benefits of mulch to more of the root zone. The workhorses of a root system, the fine root hairs, are better developed and there are more of them when growing beneath wood chips than beneath turfgrass. What is a good size for a mulched bed?  At a minimum, mulched areas should extend out at least 4 feet from the tree trunk.

High temperatures can contribute to plant stress but incorrect mulching need not be one of them.  Find out more about mulching by following this link: http://extensionpubs.unl.edu/publication/9000016361444/mulching-the-landscape/ .

Gardening with Children

When gardening with children, it’s important to encourage use of all the senses. 

▪For touch, experience plants that are soft, such as lamb’s ears (Stachys); prickly, like pumpkin on a stick (Solanum integrifolium); and stickiness of the native hedge apple (Maclura pomifera). 

▪When it comes to fragrance, we often think of flowers, but leaves and fruit are fair game too. Black walnut (Juglans) leaves and nuts have a distinct pungency that helps with identification.

▪Encourage appreciation of sound as wind moves through tall grasses or causes rattling of the pods of false indigo (Baptisia).

▪Set up your own taste test by pairing store-bought strawberries against their juicy fresh-from-the-garden counterparts so children know what food should really taste like.

▪We use the sense of sight all the time but many of those times we fail to really SEE things. Engage children in the search for the wishbone at the center of wishbone flower (Torenia) or counting the number of pollinators on a wildflower.

Consider planting a themed garden to mix things up and add some fun:

▪An alphabet garden can be made up of both food and ornamental plants (“a” is for alyssum, “b” is for beans, etc.)

▪A zoo garden features plants that have an animal in their name. Some fun plants are zebra grass (Miscanthus), hen and chicks (Sempervivum), and pigsqueak (Bergenia).

▪ Grow cilantro, tomatoes, hot peppers and onions in a circular garden (to mimic the round shape of a tortilla) to make a salsa garden. 

▪Plant a pizza garden by growing basil, tomatoes, sweet peppers and onions. Then have a pizza-making party!

▪A three sisters garden is named for the Native American tradition of planting corn, beans and squash together because they benefit one another. Corn supports the beans as they climb, beans provide nitrogen (a needed plant nutrient), and squash keeps everyone’s roots cool.

Gardening with children passes along science disguised as hands-on fun.  This age old tradition creates a new generation of gardeners who can grow their own food and have an appreciation for the green world around them.

The Best Way to Remove Problem Trees

Seedling trees come up in the oddest places, and in some cases, totally unnoticed.  In the neighborhood I drive through, I observed a mulberry tree growing up through a shrub rose.  The mulberry thrived, gradually completely shading out the rose.  Eventually the rose owner noticed the mulberry and tried to remove it, resulting in the loss of both plants.  The key lesson here, other than mulberries being aggressive growers, is that by simply taking note of what is going on in the landscape and taking action while problem plants are young, time and effort is saved later.

Tree seeds have multiple ways of dispersing—wind and birds being the most common. Mulberry, boxelder, ash, silver maple, cedar and Siberian elm are often the worst culprits, producing a huge number of seeds and sowing themselves into cracks, finding a place amidst desired plants and insinuating themselves in the tiniest patch of bare earth. The flying saucer-shaped seeds of Siberian elm and the winged seeds of silver maple are excellent mechanisms for wafting into new places. The seeds of mulberry and cedar are a favorite food of birds, with the seeds moving unscathed through their digestive tract. Wherever birds roost, droppings are deposited along with a healthy dose of fertilizer to get the seedlings off to a good start.

Seedling trees that come up in lawns are easily managed just by the act of mowing, killing them at a vulnerable size. Shrub and flower borders, vegetable gardens and containers aren’t mowed so require diligence on our part to keep volunteer trees from becoming monsters.  Approaching this task is easier when trees are small, making the chainsaw and loppers unnecessary, especially when complete removal consists of pulling out seedlings between the thumb and forefinger. Larger trees that have been cut down, only to re-sprout, have enough sugars stored in their root system to make removal by pruning alone unlikely. When digging out problem trees is not a possibility, drilling multiple holes into the stump and applying a herbicide is a simple way to address problem trees.

If your own financial circumstances allow for the hiring of landscape management professionals, then having eyes on the landscape isn’t going to be a problem. Lacking a professional landscaper, monitoring what is going on in the landscape is the next best thing to address potential issues before they become real problems.  

 Nebraska Extension Master Gardeners can answer your gardening and plant questions!  The horticulture helpline is available for questions from the public at these dates and times:

Mondays, 9 a.m. to 12:00 noon, Washington County Extension, 402.426.9455

Tuesdays, 1:00 to 3:00 p.m., Cuming County Extension, 402.372.6006

Wednesdays and Fridays, 9:00 a.m. to 12:00 noon, Dodge County Extension, 402.727.2775

Peach Leaf Curl

Peach leaf curl is prevalent this spring.  The fungal pathogen, Taphrina deformans, causes leaf puckering and unusual coloration, with bright red, yellow, lime green, or a combination of all three colors on one leaf.  Infection occurs at bud swell and bud break, when spores, overwintering on twigs and buds, infect emerging leaves. The distortion of leaves inhibits photosynthesis and early defoliation occurs, all of which affects the tree’s ability to produce peaches. If infection is severe and occurs over several growing seasons, the disease weakens the tree.

Cool, wet springs are highly conducive to the development of peach leaf curl on peaches and nectarines.  While the disease tends not to infect the fruits, fungal infection of the fruit is possible when temperatures and precipitation levels continue to favor the pathogen. As the disease matures, leaves become thickened and covered in powdery spores. Affected leaves may drop from the tree or continue to hang on branches.

Once the fungus is present on leaves, fungicide applications do not provide much in the way of protection or control. The key to keeping disease incidence low is to target overwintering spores. Dormant oil is a heavy, viscous oil that works by suffocating fungal spores on twigs and buds. Applications are best applied twice, once in late November and the second in late March when temperatures are above freezing. Other fungicide options include chlorothalonil and copper-containing fungicides.

Growing Asparagus

Cooks love the earliness that fresh asparagus provides. Gardeners love it because it’s perennial and relatively worry-free. If you’ve not grown asparagus, this spring would be a good time to plant a few crowns to find out for yourself just how easy it is to grow.

Asparagus can be started in one of two ways.  Seeds are an economical way to go but add an extra year onto when harvest can begin. Asparagus can also be started from year-old crowns purchased from garden centers, box stores or catalog companies. ‘Mary Washington’ is an asparagus variety that has been around since 1949 and is still readily found today. The ‘Jersey’ series of asparagus, consisting of ‘Jersey Knight’ and ‘Jersey Giant’ are highly touted but lack hardiness when temperatures are below -30° F and snow cover is minimal.  Newer varieties better suited to our winters include ‘Purple Passion’ and ‘Viking KB-3’.

Asparagus is a dioecious species, meaning there are male plants and female plants.  Female plants produce red “berries” that drop to the ground, seeding new plants into unexpected places like creeks, ditches, and roadsides. If not sprayed with a pesticide, spears can be harvested from these wild plants. (My brother has a list of locations of wild asparagus and jealously keeps it secret!) While the berries are not poisonous, they are inedible. Male plants tend to live longer and produce more spears.

Because asparagus is a long-lived plant, care should be given to soil preparation. A pH of 6.5-7.0 is best for good growth.  Sulfur may be added to bring the pH lower if the pH is above 7.0. Asparagus plants appreciate a deep loamy soil so work compost into the site if the soil is sandy or clayey.  Soils in our area tend to be abundant in phosphorus and potassium, so a 30-0-0 fertilizer applied at of a rate of ½ pound per 100 square feet provides the nutrition for good growth. 

To plant asparagus crowns, dig a trench 6-8 inches deep and 12 inches wide.  Spread out the roots around the crown and add two inches of soil.  (More soil is added as plants grow.) Crowns should be spaced 12-18 inches apart in rows 5 feet apart. 

Weeds and the asparagus beetle are two common problems. Keep in mind that tilling to remove weeds has the potential to damage asparagus crowns too.  Hand-pulling weeds and mulching with shredded newspapers or wood chips keeps weed numbers low while plants are establishing.  Once the stems develop ferns, the plants will shade out would-be competitors. The asparagus beetle, both the adults and the immatures, feed on the spears, stems, and foliage of asparagus, causing bending or twisting of the spears, along with brown spots from the feeding site. If damage from the asparagus beetle warrants control measures, use an insecticide labeled for use on edible crops such as insecticidal soap or spinosad.

Asparagus can be harvested during its third growing season.  Bend the spears to snap them off or use a knife to do a clean cut. Once most of the patch has more pencil-sized spears than plump ones, it’s time to quit harvesting and let plants re-build their reserves.  Cut the stems and ferns back to the ground in the fall after the entire plant has turned brown.  This allows the plant time to transport carbohydrates from the leaves into the root system.  This also removes overwintering eggs from the asparagus beetle.

More information may be found here:  https://extension.umn.edu/vegetables/growing-asparagus .

Nebraska Extension Master Gardeners can answer your gardening and plant questions!  The horticulture helpline is available for questions from the public at these dates and times:

Mondays, 9 a.m. to 12:00 noon, Washington County Extension, 402.426.9455

Tuesdays, 1:00 to 3:00 p.m., Cuming County Extension, 402.372.6006

Wednesdays and Fridays, 9:00 a.m. to 12:00 noon, Dodge County Extension, 402.727.2775

Vegetable Gardening 101

Nothing provides greater satisfaction than to grow your own food.  It’s also really easy to start, with a small investment in some seeds, a few transplants, and a container or plot of land.

A basic requirement in vegetable gardening is a clear understanding that there are cool season vegetables—those that grow and produce best when temperatures are chilly and frost is still a common thing—and warm season vegetables—those that grow abundantly when frosts are past and temperatures are warm.  Cool season vegetables include kale, lettuce, peas, radishes, broccoli, cauliflower, cabbage, potatoes, onion, and spinach, to name a few.  Warm season crops are comprised of eggplant, pepper, tomato, tomatillo, beans, okra, New Zealand spinach, cucumbers, melons, corn, basil, summer squash, and winter squash.

Cool season vegetables will develop flower stalks and fail to produce if planted when temperatures are too warm.  Likewise, warm season vegetables will need protection if planted when frosts are still common. Mother’s Day serves as a good date to gauge if it’s time to be planting warm season vegetables and marks the end of spring planting of many cool season crops. Gardeners have the added benefit of getting in a second crop of cool season vegetables by planting them in late August. Though temperatures may be still warm in late August, cool season seedlings will benefit from lattice or some other temporary shade structure until temperatures cool.

From here, it is helpful to know which vegetables can be started by directly sowing seeds into the garden and those that need a head start, such as those started early indoors or purchased transplants from the garden center.  Lettuce, peas, spinach, radishes, kohlrabi, beans, cucumbers, melons, corn, basil, and squash are easily directly sown from seed into the garden. Those that benefit from the extra time provided by starting them early indoors are broccoli, cauliflower, cabbage, Brussels sprouts, eggplant, pepper, tomato and tomatillo.

Many new gardeners purchase every vegetable for their garden as cell-pack transplants.  Not only is this a costly way to vegetable garden, it also limits the vegetable varieties to choose from. Starting seeds inside to transplant later into the garden or to be directly sown offers a cost savings and a tremendous variety of possibilities missing from cell-pack choices. An excellent resource for getting started is from Iowa State University Extension, “Planting a Home Vegetable Garden,” available at: https://store.extension.iastate.edu/product/4134 .

Want to know more about vegetable gardening and the possibilities that seeds offer?  The Nebraska Extension Master Gardeners in Washington County are teaming up with the Blair Library to sponsor a seed library. People can check out seeds to grow in their garden, then return collected seeds to the library at the end of the gardening season.  Kickoff for the new seed library is a seed exchange, Saturday, May 18, from 1:30 to 3:00 p.m. at the Blair Library, 2233 Civic Drive. An “Ask the Master Gardener” table will be featured, along with a program on “Beginning Vegetable Gardening” by me at 1:30 p.m.

Nebraska Extension Master Gardeners can answer your gardening and plant questions!  The horticulture helpline is available for questions from the public at these dates and times:

Mondays, 9 a.m. to 12:00 noon, Washington County Extension, 402.426.9455

Tuesdays, 1:00 to 3:00 p.m., Cuming County Extension, 402.372.6006

Wednesdays and Fridays, 9:00 a.m. to 12:00 noon, Dodge County Extension, 402.727.2775

 Managing Weeds in the Garden

Weeds may be our least favorite topic but still one of the driving forces behind phone and email questions right now, with “How do I kill...?” leading the discussion. Weed identification may seem immaterial, after all, the consuming focus is to be rid of the pesky plant, but in reality, this should always be the first step.  Why?  Because determining if the weed is an annual or perennial will help to direct the most effective management strategy.

Let’s start with annual weeds. In this category we have foxtail, crabgrass, henbit, Pennsylvania pellitory and speedwell to name a few.  For annual weeds, plants rarely expend much energy to develop a robust root system.  Instead, the plant’s life cycle depends on producing copious amounts of seeds before the growing season ends and the weed dies. Keep in mind that herbicides work best when translocated into the root system, resulting in effective management of the weed. With annual weeds, however, movement within the plant is upward and little in the way of herbicide is moved into the roots.  Dieback of the foliage occurs but the weed can and does grow back.

A better strategy would be to make use of pre-emergence herbicides for annual weed management. A pre-emergence herbicide targets germinating seeds, killing them before they even break the soil surface. For winter annuals like speedwell and henbit, the application of a pre-emergence herbicide takes place around September 1. For warm season annuals like purslane and spotted spurge, an application around May 1 is best.

Perennial weeds are different in that their root system survives our winters, putting on fresh growth each spring.  Brome, dandelion, ground ivy, wild violet and stinging nettles are just a few of the many perennial weeds. For perennial weed management, their winter survival strategy can be used against them. In the fall, as perennials ready for winter, transport of sugars into the root system ensures survival for plants.  Post-emergence herbicides applied at this time are very effectively moved into the root system along the sugar pathway. The result is more effective management. Does this mean we shouldn’t try to manage weeds in the spring and summer?  Not necessarily. After all, the plants will be growing robustly during this time, so the point is to use herbicides to slow growth while recognizing that management efforts will have greater efficacy with a fall application.

Yellow nutsedge management requires a different strategy, utilizing a post-emergence herbicide containing the active ingredient either halosulfuron or sulfentrazone.  Application needs to take place before June 21 (the summer solstice) to bypass the plant’s ability to create underground structures, called nutlets, that are resistant to herbicides.

Patience is a virtue when dealing with any kind of weed issue. Rarely does one application of a herbicide take care of the entire problem. Identifying the plant in question leads to an understanding of the plant’s life cycle, which then directs management strategies. Weeds of Nebraska and the Great Plains from the Nebraska Department of Agriculture is a great resource for identifying weeds, with color pictures and descriptions of the plant. Order forms to purchase the book may be found here: http://www.nda.nebraska.gov/forms/nw11.pdf .    

Mulch Volcanoes—A Harmful Practice for Trees

Too often the mindset is if a little is good then a lot must be better. So it goes with the spring task of mulching. A “mulch volcano” is the tongue-in-cheek term given to those copious heaps of woodchips surrounding a tree.  No one knows exactly where this harmful practice came from but all it takes is for one person in a neighborhood to do it and suddenly this ill-advised practice is everywhere.

There are two detrimental effects to mulch volcanoes. First, roots respire, meaning they take in oxygen and release carbon dioxide.  This exchange of gases, as it is known, takes place in the upper 18 inches of soil.  It’s no accident that roots proliferate in the top 18 inches because this is where oxygen is most readily available.  Bring in a boatload of mulch and suddenly the lower roots no longer have access to oxygen.  This leads to stressed and dying roots which in turn stresses the tree.  A stressed tree has less defenses than their properly-mulched counterpart, leading to susceptibility to otherwise-minor insect and disease problems. 

The second detrimental effect of a mulch volcano has to do with the tree trunk. Tree bark is well suited to protecting the trunk from sunlight and wind.  Mammoth piles of mulch surrounding a trunk, however, keep bark constantly moist, fostering decay.  Over time the bark rots, exposing the conductive tissue beneath the bark to decay as well. This negatively impacts the trunk’s function to move water upward/sugars downward and the structural integrity of the tree.  (I once walked through a neighborhood after a windstorm and every tree lying on the ground broke below the mulch volcano, showing lots of symptoms of decay.

Written as an equation, it would appear as:

Too much mulch = stressed roots + rotting trunks → unhealthy trees → increased susceptibility to (otherwise minor) insect and disease problems + structural instability = more $ to treat + increased probability of tree death.

What is proper mulching?  A two to three inch layer of shredded bark or woodchips, starting two inches from the tree and extending out to a distance of 4 feet from the trunk is best. Never use landscaping fabric as this interferes with the exchange of gases at the root zone. Mulch decays over time, which enriches the soil, so renew the mulch as needed to maintain a depth of 2-3 inches.

What can you do?  Ask your landscape manager about their tree mulching practices and, if it is done incorrectly, ask them to re-do it. Neighborhood associations and SIDs can share information within their communities to educate those who like to do the work themselves. Make sure your own trees are properly mulched, talk about it with others and then show it off!

The benefits of proper mulching are manifold—suppression of weeds, cooler soils in hot weather, protected soils in cold weather, keeping string trimmers and mowers away from tree trunks, and fostering microbial activity for healthy roots.  The time and effort to properly mulch is well worth the effort for vigorous growth and a happy tree. 

Henbit, Ground Ivy and Speedwell

Three weeds we see at this time of year resemble each other so closely that it is often confusing as to which is which. Henbit, ground ivy, and speedwell are flowering right now so are easy to notice.  I’ll admit, conversations about weeds are some of people’s least favorite, but talk we must and to this end identification of the weed is a key first step.  Why? After all, isn’t a weed a weed and all weeds should be eradicated by any means? Like most things involving plants, it’s just not that simple. Remember that pollinators like these plants for the nectar they provide in early spring.  Devoting a small space to these plants is an excellent way to help them out while minimizing square footage overall. So if management is a must, identifying the plant first leads to information about its life cycle, which in turn gives clues about effective ways to manage it.

Henbit, Lamium amplexicaule, is a winter annual and a member of the mint family. The purple flowers begin in March and continue through May.  You’ve probably seen this plant numerous times—it is the carpet of purple across fallow fields. It can be distinguished from ground ivy, which also blooms purple, by the leaf attachment. The upper leaves on henbit are sessile, meaning there is no stalk attaching the leaf to the stem.  (A way to remember this trait is that the hen squats on the stem!) Henbit spreads primarily by seeds.

Ground ivy (Glechoma hederacea), also a member of the mint family, differs from henbit in that it is a perennial. All leaves of ground ivy will have a stalk (called a petiole) attaching it to the stem.  Ground ivy grows very well in urban settings, preferring shaded sites but will also show up in rough areas, such as roadsides. Ground ivy will spread by seed but it is more common to see the plant spreading by root development along stems.

Speedwell, Veronica agrestis, is not in the mint family at all, so the plant won’t have a strong aroma when mowed.  Mowing really isn’t a means of management because speedwell really hugs the ground.  The flowers of speedwell are tiny, just 1/8 of an inch across and sky blue in color. A winter annual, it shows up in areas of thin turf.  Speedwell spreads by seed.

Since henbit and speedwell are winter annuals, a pre-emergence herbicide applied around Labor Day in the fall does an excellent job of keeping weed numbers down.  A three-way herbicide (one that has 3 herbicides in one product) and herbicides containing triclopyr provide some post-emergence control for henbit and speedwell.  Triclopyr is a good management option for ground ivy with better control achieved when the herbicide is applied in the fall, interfering with the plant’s ability to store food for winter.

Flooded Vegetable Garden Plots

Looking forward to the vegetable garden this spring, it’s easy to think that now that the flood waters have receded, our gardening season can carry on as usual.  While many of the callers to Extension are aware of potential dangers of gardening on a flooded site, the exact way forward is a little unclear.  Here is a synopsis of how flooding affects food safety in our vegetable gardens and orchards.

Flood waters carry contaminants, like E. coli and Salmonella, and an array of other stuff, like petroleum products, pesticides, dirt and sand. Mother Nature has in her toolkit some truly wondrous ways of dealing with contaminants, sunlight and soil microbes being two of them.  It takes time for these to complete their work, however, so until contaminants are broken down and degraded, keep in mind some food safety guidelines.

Much of what we know about food safety, flooding, and contamination come from research conducted on the use of fresh manure in gardens. From this research, two blocks of time are key—the 90 day interval and the 120 day interval.

The 90 day interval starts when flood waters recede and extends to when harvesting for eating takes place.  This refers to fruits and vegetables not in direct contact with the soil.  So tomatoes (staked), peppers, eggplant, cucumbers (trellised), sweet corn, tomatillos, apples, pears and grapes fall in to this category.

The 120 day interval follows the same concept but is extended to those fruits and vegetables that are in direct contact with the soil.  This includes strawberries, tomatoes (un-staked), muskmelon, watermelon, radishes, lettuce, carrots, potatoes, spinach, asparagus, cucumbers (un-trellised), morel mushrooms, herbs, and rhubarb. If the interval extends beyond harvest readiness, then discarding of the produce is recommended.

Other important considerations:

                ▪Seeds and transplants can be planted into previously flooded soils before the time interval has elapsed as long as the harvest extends after the 90-day or 120-day intervals.

                ▪Removal of transported soil and sand from the garden site does not negate the 90-day and 120-day rules.

                ▪Cooking/canning kills some bacterial and viral contaminants from floodwaters but not all.

                ▪Some seasonal fruits and vegetables will not be candidates for eating this spring, perhaps even this year.

                ▪Harvesting before the interval has passed to store the produce in the refrigerator to wait out the remaining time does not count. Sunlight plays an important role in degrading contaminants.

                ▪Vigorous scrubbing and chlorinated solutions destroy produce quality and do not dislodge all bacteria and contaminants from cracks and crevices in fruits and vegetables.

Be Mindful of Flooded Areas When Hunting Morels

As morel mushroom hunting season approaches, be mindful of food safety.   It’s important to remember flood waters don’t carry just water.  There is a host of unsavory things that are downright dangerous—

                ▪Human disease pathogens from raw sewage,

                ▪Pesticides carried from farm fields and lawns on soil particles and plant residue,

                ▪And rubber and petroleum products from cars, boats and farm equipment. 

While there is NO washing technique that will completely remove all contaminants from morels, the heat from cooking them will likely kill human pathogenic bacteria and viruses. This is not true for pesticide and petroleum residues.  These products can be harbored in the tiniest crevices and tissues of the morel and are extremely resistant to removal by washing.  Since we can’t know all of the contaminants flood waters carry, it is far safer not to eat morels gathered from flooded areas.

Morel mushroom hunters should take note of their usual gathering sites.  High ground is going to be best for searching for morels as these sites are less likely to have been flooded.  If corn stalks and grass are caught high around brush and fences, this is a clear indication the site was flooded and morels should not be gathered. Again, it’s better to ere on the side of food safety.

For those who have been gifted or have purchased morels, be sure to ask questions from the gatherer about where the morels came from.  People with compromised immune systems, such as children, the elderly and those who are ill, are adversely affected by the flood water contaminants that morels can harbor.

Never use soap to clean morels. Instead use 2 tablespoons of bleach to one gallon of water for washing, followed by thorough rinsing with clean water. 

While it is hard to miss out on this tasty spring treat, if we receive no more flooding, morel mushroom aficionados can expect gathering with no reservations next spring.  For more flood resources, go to flood.unl.edu

Flood Recovery and Plants in the Landscape

The flooding and subsequent ponding has a profound effect on trees and shrubs in the landscape. The contaminants these waters carry negatively impact vegetable garden sites and orchards.  Here are some flood resources to address residents’ concerns.

Food safety in vegetable gardens and orchards after a flood*: https://grobigred.com/2019/03/22/gardenflood/amp/?__twitter_impression=true  by Nebraska Extension Urban Ag Educator John Porter

Turf Recovery After Historic Flooding: https://turf.unl.edu/turfinfo/3-25_Flood_Recovery.pdf by Roch Gaussoin and Bill Kreuser, University of Nebraska-Lincoln

Understanding the Effects of Flooding on Trees: http://store.extension.iastate.edu/product/Understanding-the-Effects-of-Flooding-on-Trees-Sustainable-Urban-Landscapes-PDF , Iowa State University Extension

Helping Flooded Trees and Shrubs: https://www.ag.ndsu.edu/publications/lawns-gardens-trees/helping-flooded-trees-and-shrubs , North Dakota State University Extension

*With morel mushroom hunting season approaching, be aware that mushrooms collected from areas impacted by flooding should not be eaten. This would also be true for other wild edibles, as well as domestic perennial crops like asparagus and rhubarb.

For more resources on flooding, go to flood.unl.edu or email questions to floodresponse@unl.edu .

Flooding and Ponding around Trees

The 2019 spring flood has had a devastating impact for all parts of the landscape, including trees.  While the extent of the damage to trees may not be realized for years, how and if trees survive depend on several factors.

▪Certainly that the floods came when the trees were dormant is a factor in their favor. Flooding is always hardest on actively growing trees.

▪The length of time tree roots are submerged will determine whether they can survive.  The water left behind after a flood (ponding) is more detrimental to trees because water replaces air in soil pore spaces.  Since roots require oxygen to complete their metabolic processes, the lack of oxygen in waterlogged soils causes root death.

▪Some tree species, like the baldcypress, cottonwood, and willow tolerate the waterlogged conditions that flooding brings, mainly because they are able to regenerate new roots relatively quickly.  Others, such as sugar maple, redbud, shagbark hickory and spruce are intolerant of waterlogged soils and will show symptoms of yellow leaves, lifting bark, brown needles, defoliation and crown dieback because of their slow regeneration of new roots.

▪Healthy trees, like healthy people, naturally have more resiliency when adverse events happen. The more robust the tree, the better able it will be to marshal the defenses necessary to survive the flooding. Healthy trees will have greater root regenerative capacity and more resistance to secondary insects and diseases that overcome unhealthy trees.

▪The stuff the floodwaters carry is a factor when determining if trees will survive.  Deposited soil, raw sewage, petroleum products and a host of other contaminants are challenges to root survival.

What Can Be Done

Replace soil around flood-exposed tree roots. Likewise, remove all flood-deposited soil around trees, clearing away all excess around the trunk itself and continuing beyond the dripline. For trees toppled because of dislodged roots, small and medium-sized trees can be righted and staked for stabilization. Remove rock, landscaping fabric, and mulch (if it hasn’t washed away) to allow sunlight and air circulation help with water evaporation from soils. Plan to remove broken branches at the proper pruning time of April, May or June. Although it is human nature to want to help, trees stressed due to flooding should not be fertilized.

 More information about how floods impact plants may be found here: https://flood.unl.edu/horticulture .

What Kills Trees

Trees in native undisturbed sites live, on average, to be about 150 years old.  Downtown trees have a life expectancy of 7-17 years; suburban trees 30-40 years; and rural trees 60-70 years.  Why is there such a difference in life expectancy between trees in native sites than those in disturbed sites? Certainly there are acute factors, like hail, herbicide drift and insect infestations that can kill trees but the chronic issues overwhelmingly pre-dispose trees to shortened lifespans.

While difficult to see, pre-disposing effects are basically unhealthy environments. This leads to unhappy trees with dysfunctional roots.  Some common pre-disposing factors include:

▪Trees are planted too deep

▪Grade changes around existing trees

▪Soil compaction

▪Trees are overwatered

▪Exposure to long term drought

▪Live in confined root spaces

▪Have girdling roots

▪Are not winter hardy

▪Are not adapted to growing in soils with a high pH.

Most of us do not recognize a tree in decline until 12-20 years after the tree has been planted. Amazingly enough, unhappy trees will grow but lack the energy to really thrive. Too often, this means conditions are not reversible and the problem cannot be remedied.  What tree owners do notice are acute conditions—leaf scorch, chlorosis, early leaf shed, smaller leaves and reduced tree stability—symptomatic of the larger problem of unhappy trees with dysfunctional roots.

Trees have a limited ability to adapt to adverse growing conditions. Those living in adverse conditions are subject to a decline spiral, succumbing to short term “problems” that healthy trees growing in good environments can readily withstand. If we select, plant, and manage trees with the intention that they not only survive but thrive, many tree problems are preventable, resulting in longer lived trees.

Check out Cornell’s Woody Plant Database to search for trees and shrubs suited to specific conditions:  http://woodyplants.cals.cornell.edu/home .

What is Nebraska Extension ProHort Education?

ProHort, short for Professional Horticulture, is research-driven education for individuals in the tree, lawn, landscape maintenance, and garden center industries, as well as anyone who wants to hone her/his skills in the areas of botany, insects, soils, landscape design, plant disease, trees, wildlife damage management, turfgrass, and Integrated Pest Management (IPM). While people participating in ProHort education train right alongside Nebraska Extension Master Gardeners, there is no volunteer component associated with ProHort education nor do people have to apply to participate.

Classes begin on Wednesday, March 6 at Dodge County Extension, 1206 West 23rd Street in Fremont and continue for an additional five consecutive Wednesdays, culminating in a diagnostic lab on Wednesday, June 5.  Altogether, thirteen topics are covered during the course, with a new topic each morning and moving to a different topic in the afternoon.

Classes are taught by educators from Nebraska Extension, as well as the Nebraska Forest Service. Classes qualify for continuing education units (CEUs) required for re-certification with the Nebraska Arborists Association and the International Society of Arboriculture.

Those wishing to participate in ProHort Education have two options—classes are offered as stand-alone training sessions at a per-topic cost or they may opt to attend the entire course, which is a savings over the cumulative per-topic cost. The ProHort handbook is provided to those attending the full course.

More information and registration information may be found on the Nebraska Extension in Dodge County Facebook page or by contacting me at 402.727.2775.

Plan…Plan…Plant!

In carpentry, there is an old adage urging us to measure twice and cut once. The same can be said when it comes to plants.  Planning is the least expensive of the plant selection process, simply requiring a little of our time to talk to experts and glean information from catalogs and web sources.  I’ve never had a client say, “Gosh, I’m really sorry I planned and did the research!”  Rather, I hear from clients who didn’t adequately plan and are now dealing with how to help plants survive or costly removals.

Most plant failures come from a shortfall in adequate information.  A sibling was ready to plant a Japanese maple in their front yard, the site of new construction with poor soils and little in the way of wind blockage, until someone (me!) mentioned this wouldn’t work. Knowing which plants can handle the rough places and which need more protection plays a huge role in plant selection.

Another example of inadequate planning is when plant success creates an issue, such as the cute little blue spruce planted next to the driveway. That little tree that was so adorable is now covering the driveway and obstructing the driver’s site line for vehicle and pedestrian traffic. I once watched a neighbor struggle with this very issue, first pruning out the lower limbs and then disliking the result so much that the tree was removed. A $1000 bill later fixed the safety problem but not without cost to the wallet and loss of a healthy and handsome tree.

Nebraska Extension experts, Extension publications, garden catalogs and garden centers are good places to start.  When doing a Web search, type in the subject followed by the phrase “site:.edu” to narrow the search to research-based information.  The closer the area is to your location, the better fit for your own growing conditions. Keep in mind that listed plant dimensions are for optimum growing conditions, which the Midwest is not, so figure 80% of that number will give a better indication of the height and width of the plant, allowing you to space plants accordingly.

Be aware of glowing terms that don’t give a true picture of what the plant is like.  “Spreading” can be another word for rampant or invasive. The terms “compact” or “dwarf” are relative terms, meaning that a compact burning bush is not a neat and tidy two foot tall shrub.  It simply means a compact burning bush will be smaller than a regular burning bush (which grows to eight feet tall and wide!)

New projects are a great time to address soil conditions and the grade of slopes, which are very difficult to correct after plants are planted.  Adding compost to loosen clay soils and beef up sandy ones should be done early to ensure plant success.  Changing the grade should be done early, too, to keep from damaging the roots of established plants.  By doing the research early, you’ll be better informed to discard ideas for bringing in or removing soil around established trees, which can kill them.

Taking Care of Poinsettias

I had a client call me one September day and asked if it was time to bring her poinsettia into the light. Oh yes and by the way, she mentioned the plant had been stored in the closet for the past nine months. Hmmm… On the positive side of things, I thought it was great she was aware that the absence of light instigated the poinsettia’s coloration. Still, after 9 months with no water and sunlight, it was safe to say the plant was toast and it was best to throw it out.

How does one go about keeping a poinsettia, you ask?  First, the newer hybrids are better than ever about keeping their leaves and colorful bracts (the flowers are the tiny yellow things at the center) well into March.  So it’s no big task to keep them in a bright window with regular watering to enjoy the poinsettia for quite some time.

Once the stems lose a lot of their leaves through senescence (the natural aging and loss of leaves) or because you forgot to water it once, you have two options for moving ahead.  One is to cut back the stems by half.  The poinsettia is a shrub, so you will get lots of new shoot growth from the shortened stems. The other option, and one that takes a little finesse, is to make it into a lollipop. Called a standard, the poinsettia can be trained into a single tall stem with a ball of leaves at the top.  A poinsettia standard is created by selecting a strong, upright stem and then removing all of the remaining stems. Encourage new growth at the top by removing sprouts along the stem.

Poinsettias are native to Mexico and so do wonderfully during our hot summers.  Before moving them to their outdoor location, make sure there is no danger of a late frost and then acclimate them to the outdoors through the process of hardening off. Once outdoors, plants can be moved to larger pots, fertilized regularly and pruned according to the desired shape. 

Bring in plants before the first frost and place them in an east, west or south-facing window. Instigating the coloration of the bracts can be simple.  If room lights remain off during the evening hours AND no street or yard light leaks in through the window during the evening, the poinsettia will develop colorful bracts on its own.  Barring that, then begin the process in late September by placing the plant in a dark closet from 5:00 pm to 8:00 am and then moving it to a bright window from 8:00 am to 5:00 pm each day.  Once the coloration of the bracts begins, the plants can be moved and left in a bright window.

With all the wonderful color poinsettias provide, it’s a great indoor plant to grow your own fresh air!  More information can be found here:  https://lancaster.unl.edu/hort/articles/2007/poinsettia.shtml .

Composting—Even in Winter

Whether you are new to composting or an old hand at it, there is a technique that can, or already does, work best for you. My favorite composting adage is one supplied by Roger Swain former host of public television’s The Victory Garden: “Throw some green stuff in, throw some brown leaves in, throw in a few handfuls of dirt to activate everything, and you’ll get compost!”   People into the science of composting like to throw out terms like “the carbon-nitrogen ratio” and “aerobic and anaerobic bacterial decomposition.”  These are great terms to use, and if you understand them, can be implemented in your composting regime.  But I like Roger’s approach, mostly because it’s simple and I never want to see anyone NOT compost because it’s too complicated.

Master Gardener Wally had a novel approach.  He would dig a small hole in his flower bed and then empty in his pail of eggshells and coffee grounds.  Once the hole was filled, he would cover it with dirt and dig a new hole.  This mini-composting approach works well for people who don’t have room for a large compost pile and the soil helps mask odors to keep the critters away.  When doing this in winter, stockpile a five gallon bucket of soil and pre-dig the holes in the fall.  As holes are filled with compostable materials, throw some soil over the top and water everything so it freezes, keeping critter digging to a minimum.

Then there is Master Gardener CJ’s approach to composting.  CJ sends carrot peels, eggshells and other compostable materials through her food processor, along with a little water, to make a slurry.  (Keep in mind that the smaller the composting material, the quicker it decomposes.) This slurry is poured in a bucket, brown leaves are added, a trowel of soil thrown over to let the good bacteria activate the decomposition process, and repeated, layer by layer.  Storing the bucket in the garage ensured decomposition was working, even on some pretty cold days. At the end of winter, CJ had compost that was ready to use.

Manure from meat-eating animals should never be added to compost piles as diseases from these animals can transfer to humans. Turning the pile often helps the aerobic bacteria do their job more efficiently, resulting in faster composting.

Gardeners like to call compost “black gold” and rightly so since it improves soil and makes plant roots happy. Burning plant roots with excess nitrogen isn’t as much of a worry when using compost, which can happen when using manure.  Best of all, composting takes time and effort, but not really much in the way of money, so it is a great way to make your own black gold!

How to Become a Nebraska Extension Master Gardener

(Part 3 of 3)

Nebraska Extension Master Gardeners are Extension-educated volunteers who make a difference in their communities, reaching people from all backgrounds and ethnicities about research-based gardening information. Knowing lots about gardening before joining the program is not a requirement.  Becoming a Master Gardener involves a love of learning and the ability to volunteer to share gardening knowledge with others.

The first step in becoming a Master Gardener Intern is to attend an informational meeting.  This will be held Friday, January 11, 2019 at 3:00 pm at the Dodge County Extension Office, 1206 West 23rd Street in Fremont. At this no-obligation meeting you will find information on the class schedule for 2019, the number of volunteer hours required, applications to the program, and assistance in determining if this volunteer program is a good fit for you.  You will also get a chance to visit with a Master Gardener to learn of their experience in the program. Applications to the program are only available at this meeting, so if you plan to attend, please let us know you are coming by calling 402.727.2775 or emailing kcue2@unl.edu.

Master Gardener applicants are interviewed in a fun and welcoming environment.  Interns will be assigned a Master Gardener mentor to help with transitioning them through the program. Classes begin on March 6. The cost of the education is $175 and includes the Nebraska Extension Master Gardener Handbook, a t-shirt, name badge, and hand-outs.  If this fee is a challenge for you, other options will be shared at the informational meeting. 

Master Gardeners share a strong sense of fellowship and purpose, helping people in their community and county create environments that are healthy, productive and diverse.  Hope to see you at the informational meeting!

What about the Horticulture Education for Extension Master Gardeners?

(Part 2 of 3)

Nebraska Extension Master Gardeners are Extension-educated volunteers who make a difference in their communities by educating people of all backgrounds about research-based gardening information. Programs across the nation are set up on a one-for-one basis, with 1 hour of volunteer time for each hour of education received.  In Nebraska, Extension provides 40 hours of education to each Master Gardener volunteer in return for 40 hours of their volunteer service.

Not sure if you have enough gardening experience to qualify for the Master Gardener program? This isn’t an issue. Nebraska Extension closes any gardening knowledge gaps by providing research-based education. Topics covered include botany, soils, insect pests, plant diseases, weeds, turfgrass management, tree pruning and growing vegetables, plus a broad array of other gardening topics. All gardening education will be specific to the region, with updates on new/emerging problems. Instruction consists of lectures, labs and reading assignments and all classes are taught by Extension educators who are experts in their field.

Besides a world class education, Nebraska Extension Master Gardener volunteers maintain their connection to Extension through continuing education and project activities.  Most importantly, they enjoy fellowship centered on a love of gardening and sharing that enthusiasm with others.

Next: Part 3 of 3, How do I become a Nebraska Extension Master Gardener?

What are Nebraska Extension Master Gardeners?

(Part 1 of 3)

Nebraska Extension Master Gardeners are Extension-educated volunteers who make a difference in their communities, reaching people from all backgrounds and ethnicities about research-based gardening information.  While beautification of outdoor spaces is one of the happy consequences of their volunteer efforts, Master Gardeners do so much more: 

▪They work with child care centers and school programs to start youth on a journey of lifelong gardening and ensure the skills necessary to have access to fresh food. 

▪They serve as consultants to community and food pantry gardens.

▪Master Gardener volunteers work with garden clubs and school groups to foster, plant, and  maintain habitats for pollinators.

▪They answer questions from the public about gardening-related topics through local Extension offices via the horticulture helpline and “Ask the Master Gardener” tables.  

▪Master Gardeners provide gardening programs and demonstrations to clubs, senior citizen  centers, neighborhood associations, farmers markets, and youth groups.

Besides a love of gardening, Nebraska Extension Master Gardeners have good people skills and a strong appreciation for the research that goes into making everyone better gardeners, reducing waste that goes into landfills and using Integrated Pest Management as a means of solving pest problems, regardless if the pest is a plant disease, insect or weed.

Nebraska Extension Master Gardener volunteers have a long history of supporting the land grant mission to improve people’s lives by providing research-based education. The Extension Master Gardener program began in King County, Washington, in 1971 as an outreach to plug the gap between the demand for horticulture information and the shortfall of Extension staff to answer those questions.  Hippies and “getting back to Mother Earth” were two cultural dynamics leading to the increased demand.  Since that time, the Extension Master Gardener program has expanded across the United States, is in four Canadian provinces, and now South Korea, joining in 2011.

The Extension Master Gardener horticulture helpline and open clinic hours are:

Mondays, 9:00 am to 12:00 noon, Washington County Extension, 402-426-9455

Tuesdays, 1:00 to 3:00 pm, Cuming County Extension, 402-372-6006

Wednesdays and Fridays, 9:00 am to 12:00 noon, Dodge County Extension, 402-727-2775