Watering Trees and Shrubs

Andrea Burns
Ford County Extension Agent

This hot, dry spell is causing some major concerns with trees in the area. This means homeowners should be concerned about the trees and shrubs in their landscapes and giving them extra water.

Let’s talk about how we should go about watering mature trees and shrubs in landscape settings. Established trees and shrubs will greatly benefit from supplemental irrigation during periods of drought, Water provided from an irrigation/sprinkler system used to water your lawn is NOT enough irrigation for your trees!

To maintain vigor of trees that have been growing in place for more than five years, soak the soil to a minimum depth of 12 inches, out to and beyond the drip line (The outer most leaves on a tree defines its drip line or the area defined by the outermost circumference of a tree canopy.)

This should be done every three to four weeks if it doesn’t rain significantly. You should avoid watering mature/established trees at the base of the trunk. This is ineffective and can also cause disease.

Evergreens are more prone to drought damage, especially during the winter months than deciduous trees.

However, I have looked at some trees recently that are in serious need of supplemental irrigation! These trees also don’t show symptoms of drought as soon either and can go from dry to dead in a hurry. They should be watered in the same manner.

Established shrubs should be watered so the soil is moistened to a depth of 8 to 12 inches every couple of weeks.

Newly planted trees and shrubs should be watered at planting time and weekly after the first month. They need a weekly soaking of 10 gallons to support spring- or summer-planted trees. Smaller trees and shrubs may require less, but regardless the amount should be enough to thoroughly moisten the plant’s root ball. Do not overwater.

During dry winters, the plants should be watered when the ground isn’t frozen. Always check the moisture and adjust your watering schedule based upon the moisture content.

For more information on Watering Established Trees and Shrubs or Watering Newly Planted and Young Trees and Shrubs, check out the publications on our website at www.ford.ksu.edu or contact the Ford County Extension Office. Stay cool!