KC Gardens

Plants, trees, lawns need a good soaking now

Learning how to properly water during a drought is a combination of science and art.
Learning how to properly water during a drought is a combination of science and art. The Kansas City Star

According to the U.S. Drought Monitor, the Kansas City area is experiencing a moderate drought. This confirms what we already know: We need rain.

Water is the basis for life, both ours and the plants and animals around us. Without proper moisture plants suffer. Lack of water places stress on them, which, if prolonged, can lead to death. Luckily for most of us, we can provide the needed water to get them through periods of drought.

Not all plants suffer at the same rate.

Generally plants with shallow roots and small root mass suffer first. That means plants that are younger and still establishing will suffer first. You should water trees and shrubs planted in the last three to five years.

Evergreens, none of which are native to our climate, also are the first to struggle. Spruce, pine and others tend to have less aggressive roots and tolerance for drought. Even mature plants could use a good soaking now.

Deciduous trees tend to be a little more drought tolerant, but not all are the same. Species that don’t tolerate dry conditions should be watered.

Native trees and shrubs tend to do the best. They are better equipped to handle moisture swings, and reduce the need for supplemental watering.

Perennial flowers and lawns fall somewhere in between. Now that spring is here these plants want to push new growth. A good moisture supply will help promote spring growth.

Learning how to properly water during a drought is a combination of science and art; how much is needed (science), and how often it should be applied (art). Science has taught us that the best way to water is deeply, thoroughly and less frequently. Watering deeply soaks the plants’ root profile and infrequently allows the excess to percolate out of the small pores in the soil allowing the much needed oxygen to return.

Knowing how much to apply is a challenge. How do we know when we have saturated the root profile? These guidelines may help.

Establishing shrubs will benefit from 5 to 10 gallons of water applied slowly so it soaks into the soil. Trees should have at least 10 gallons for every inch in trunk diameter. For both shrubs and trees soak the area underneath the plant’s spread to a few feet or more beyond the dripline (the area directly located under the outer circumference of the tree or shrub branches).

Lawns and perennial gardens can be soaked with an inch or more of water using a sprinkler. An inch of water soaks the soil about 6 inches deep. This is where the majority of the roots are located.

These applications made under the cooler conditions of spring should be repeated every couple of weeks. Knowing when to water again is an art; a gut feeling it is dry.

Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Got a question for him or other university extension experts? Email them to garden.help@jocogov.org or visit KCGardens.KansasCity.com.