Annuals And Perennials Articles

Annuals And Perennials

Drought Stress on Tree Image

The Deepening Drought

Even with the much-appreciated recent rains, it isn’t enough water to lift the region out of drought. There are some changes we can implement to help plants while still making the most of the water we have.

What to Water
For landscape plants, priorities for watering are placed in importance: 1. Plants planted within the past 5 years, 2, Evergreens and orchards, and 3. All other plants. New trees and shrubs are watered 3-5 gallons per caliper inch (the trunk diameter in inches) per week. Evergreens and fruit trees, along with all other landscape plants, need an inch of water, applied all in one application, per week. Be aware that dwarf and semi-dwarf fruit trees should also be watered. . . . read more

Plastic at base of Tree Image

The Intersection of Landscape Design and Call Before You Dig

The request to the 811 center was like many received—locate the utilities because the homeowner wished to DIY a new privacy fence. Once the utilities were marked, the homeowner began to dig holes for the uprights, thinking each flag marked where he SHOULD dig, instead of where he SHOULD NOT dig. After severing the utility in multiple places, a hefty fine, and costs to reinstate the utility, the homeowner came away with a new appreciation for all that goes on below the soil surface. He was lucky because none of the damaged lines affected people or property. Things could have been worse because what goes on below ground, overhead (think electrical lines), and nearby (houses, outbuildings) all impact the projects we undertake to have safe and beautiful outdoor space.

This story may cause you to shake your head, but the reason for sharing is to foster an understanding that many landscape dangers and mistakes are preventable. . . read more

Yellow Nutsedge

Now is the time to . . .

Put down grub control to manage grub damage in lawns. The end of June/beginning of July is the window to complete this task, when grubs are small and more easily managed. 

Stop using herbicides to manage nutsedge.  Nutsedge has tiny growths at the end of roots, called nutlets, that will begin growth when the parent plant is killed, making for even more plants. . . read more

ZZ Plant Image

Winter Care Of Housplants

If you grow your own fresh air, you appreciate the liveliness houseplants bring to the indoors during the long winter months. On days when I’m feeling blue, nothing lifts my spirits like taking care of my houseplants. Removing dead leaves, looking for any insect pests that I missed when bringing them indoors last fall, pinching off leggy stems for rooting later, checking soil levels, setting aside plants that require further attention, and admiring the handsome plants are just some of the tasks I look forward to. If leafy plants aren’t your thing, consider growing one of the hugely popular succulents now found in garden centers and online.  They offer the ease of growing cacti without all the thorns that make them user-unfriendly. . . . read more

Coneflower Cut Back in Spring Image

Cutting Back Plants In Fall

If you are a creature of tidiness, here is a thought to ponder. Cutting back the foliage of flowering perennials, ornamental grasses, and small shrubs is damaging to native bees that overwinter in the hollow stems of plants.  Moisture seeps down through the open ends, killing the eggs, larvae, and pupae of native bees that are set to emerge as adult bees come spring. . . . read more

Gravel Road Image

Road Dust

If you live on or near a gravel road, the dust generated from traffic is more than just annoying. Reduced driver visibility, breathing problems and eye irritation to humans, pets and livestock, reduced life to car parts and machinery, and increased cleaning costs are just a few of the many problems associated with road dust. The amount of traffic, the weight of the vehicles, and the traffic speed determine the amount of dust generated.  According to the Environmental Protection Agency (, road dust accounts for the largest source of particulate air pollution in the country.  Besides dust suppressants applied to gravel road surfaces, plants can be a part of the solution, with windbreaks providing filtration by slowing wind speed and allowing dust particles to settle. . . . read more

Stoehr Hackberry Tree

Great Plants for the Great Plains

Each year, the Nebraska Statewide Arboretum, along with the Nebraska Nursery and Landscape Association, highlight plants that are exceptional additions to Midwest landscapes.  Plants are chosen not only for their beauty but also their durability. Those headlining 2021’s picks for Great Plants for the Great Plains include:

Tree of the Year: Hackberry, Celtis occidentalis. This close relative of the elm is Dutch elm disease resistant and tough-as-nails with beautiful bark and outstanding form. It grows well in a variety of soils and windy conditions.

Conifer of the Year: Eastern white pine, Pinus strobus. This is a soft needled pine and not as prone to problems with pine wilt as other pines are. This is large tree, reaching a height of 60 feet or so with a spread of 30 feet. . . . read more

Delaware Skipper on Echinacea

Pollinators and Pollinator Gardens

Pollinators and pollinator gardens are the focus of the next GROBigRed Virtual Learning Series. Nebraska Extension Educators in entomology and horticulture will teach participants about steps to take so pollinators thrive—both from flowers and plants important to their health to insect-friendly garden practices to implement.  Why are we concerned about pollinator health? Pollinators are first and foremost critical to our food supply. Most notably, some of our favorite fruits and vegetables, like apples, peaches, cucumbers, and beans, would not exist without our pollinator friends. . . . read more

Cue  Landscape

Using Annual & Perenial Flowers to Boost Curb Appeal

When we think of flowering annuals and perennials as limited resources, using them wisely contributes to maximizing curb appeal. After all, not everyone has unlimited budgets or time to have flower color everywhere.

A word about the color green—green piques our interest in the winter and early spring landscapes, most notably because there is so little of it around (think evergreens and patches of lawn showing through the snow.) That perspective changes as landscapes green up in the spring and THEN green switches from being a focal point to becoming a background color. This transition is important because flowers show to their best advantage when placed in front of a backdrop of green. . . . read more

Perennial Garden Image

Fall Care of Perennials - Part 1

Once gardeners and gardens have survived the heat of summer, cooler weather offers an opportunity to complete some simple tasks to ensure perennial plants emerge in good health next spring.

 Cutting Back

If the foliage of perennials has been disease-free, wait to cut them back until spring. This benefits our native bees because 1/3 of native bees overwinter in cavities, which includes the hollow stems of plants. By waiting to cut back perennials until spring, these pollinators are given a fighting chance to survive. In addition, many perennials are beautiful in the winter landscape, showing off the petal-less cones of purple coneflower and the gracefully waving seed heads of prairie dropseed. Stems left in place serve as reminders where the slow-to-emerge balloon flowers and hibiscus will be in spring. Stems catch leaves and other bits of plant debris, making them self-mulching. . . . read more

Coreopsis Image

Fall Care of Perennials - Part 2

It may seem like perennials demand lots of our attention, but they are really quite forgiving, with many plants living despite, not because of, our gardening efforts. For their hardiness and beauty, we can ensure they stick around by adhering to a few guidelines.  

 Digging and Dividing

If your perennial plants didn’t bloom well or they’re crowding their neighbors, fall is an excellent time to divide plants. Some perennials, like ‘Karl Foerester’ feather reed grass, develop woody centers at the crown over time. These areas have lost their vigor and no longer send out growth, despite being dense with plant tissue. Using a sharp spade, dig the entire clump and divide the root system, being sure each division has a crown and roots, discarding the center of the plant to the compost pile. Make sure clumps are at least 6 inches across to ensure good vigor once the division has been planted.  Set the divisions in their new location, making sure plants are at the same depth as they were previous to digging. For plants like peonies, this step is critical because plants too deep or too shallow will not bloom again. Cut back foliage by half so the reduced root system's water uptake matches leaf needs. Water the transplants in their new location and mulch to delay ground freeze which allows more time for new roots to develop. . . . read more

Straw Foxglove Image

Straw Foxglove

Unlike foxglove that are biennial, straw foxglove (Digitalis lutea) is a true perennial. The light yellow bell-shaped downward-facing flowers are smaller than their biennial relatives, but what is lost in flower size, straw foxglove makes up for in reliability and ease of growth.

 Straw foxglove does best in average garden soil in a site that receives about 2-5 hours of direct sunlight daily.  Planted at the edge of tree lines, in woodlands, or where the neighbor’s garage shades your yard, this foxglove excels in challenging sunlight conditions. Its short stature, at 18-24 inches in height, makes it a good choice for the front of a shady border. Water during dry spells and mulch with a 2-4 inch layer of woodchips to keep soil evenly moist.  Spent flowers may be deadheaded or left in place to allow seeds to fall around the parent plant. . . . read more

Woodland Phlox

Woodland Phlox

Woodland phlox, Phlox divaricata, also known as wild sweet William, is a shade-loving perennial that produces lavender blue five-petalled flowers in spring.  It has a wonderfully long bloom season. In my garden, it has been sending out flowers for a solid month now.

Woodland phlox does best under trees in soils rich in humus. The plant naturalizes, gradually spreading into empty spaces when stems touching the ground root.  At just 12 inches in height, the spread is not aggressive, knitting in around other shade lovers like hosta and Solomon’s seal. Mulch plants with a 2-4 inch layer of wood chips to keep soil evenly moist and water during extended periods of dryness. . . . read more

Helenium autumnal bicolor

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. . . . read more

Tube Clematis Image

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 challenge posed by 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. . . . read more

Flood in the Landscape Image

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. . . . read more

Seeds Image

Saving Seeds

Long before the advent of seed catalogs, gardeners saved seed from their prettiest, tastiest and most promising flowers and vegetables of the gardening season, discarding the seeds from the blah, the unattractive and the poor producers.  In essence, gardeners have helped mold the shape of gardening selections, making them some of the earliest purveyors of genetic modification. . . . read more

Turtlehead Image

September Flower Power

September doesn’t have to be about chrysanthemums and asters alone.  There is a plethora of other, lesser-known, counterparts that can add flower power to the late season garden.

 Turtlehead, Chelone lyonii, has light pink to dark pink flowers that resemble, you guessed it, a turtle’s head. Serrate leaves are pointed, shiny and dark green. People are surprised to hear it is a native plant because the flowers are so very different from the daisy-type flowers prevalent now.  Plant turtlehead in a location where it receives shade in the afternoon and has soil that stays evenly moist. . . . read more

Rocks Image

The Hard Truth about Rocks at the Bottom of Planting Containers

As we get our containers ready for planting our amazing annuals or that coveted tomato plant, conventional “wisdom” dictates we must first add an inch or so of gravel.  Problematic? You bet!   

Rocks in the bottom of containers do not contribute to better draining soils and healthier plants.  Instead plant roots encounter saturated soils that don’t drain efficiently.  It all has to do with something called a perched water table. . . . read more