Week of August 15, 2022
Kathleen Cue, Extension Horticulture Educator in Dodge County
As much of the region deepens to severe and extreme drought, it is crucial to provide water to plants impacted by the dry conditions. Orchards, landscape plants, trees, conifers, shrubs, and windbreaks will need a deep soaking to survive the summer drought and increase chances for winter survival.
For fruit trees to yield the maximum number and size of fruit, adequate moisture is critical. Apple, pear, and peach trees will have smaller fruits and lower sugar content when developing during dry conditions. Sandy soils have less water-retention capabilities than clay soils, so fruit trees growing in sandy soils will struggle more during a drought than their counterparts growing in a clay soil. Likewise, dwarf fruit trees have a smaller root system, occupying less soil volume than a full-size tree growing on its own roots, and are more likely to experience adverse effects from drought.
Foresters assure us that drought conditions can impact trees up to 5 years after an event. Severe conditions reduce tree defenses and will manifest as pest and disease infestations that most likely would not have happened to healthy trees. All trees, even venerable old trees, benefit from a deep soaking. By placing the hose on trickle and allowing it to run for several hours at a time, tree root and stem tissues are fully hydrated, making them better able to withstand the onslaught of winter.
Mulching with 2-4 inches of wood chips or shredded bark keeps soils cooler and roots functioning, while also helping to retain what little moisture is there. A layer 2-4-inches deep and extending out from the trunk by at least 3 feet (further out is even better) is ideal. Stay away from creating mulch volcanoes that promote rodent damage to bark. Rock mulches increase heat around root systems and should be avoided.
Lawns made up of Kentucky bluegrass can be allowed to go dormant to save on water, which instead can be watered every other week or so with about ½ inch of water to keep crowns hydrated and alive. Fescue, deemed a drought-avoidance species because of its deep root system that taps lower sources of soil water, does not go dormant and will require water at least once a month with an inch of water to survive.
Never fertilize plants affected by drought. Not only does the root system have a reduced capability of taking in nutrients when soil conditions are dry, but most fertilizers are applied as salts, which further exacerbates dry conditions.
By taking some steps now to address the drought, food-producing and landscape plants will have greater resiliency to withstand what winter 2022-2023 sends this way.
Photo: Drought Condition (Purdue.edu)
Find more horticulture articles at Trees, Plants and Insects