Take Care of Your Trees

Trees and shrubs provide us with shade, clean air, clean water, and increased property values. During the summer months, these are the plants you want to target when watering

During the summer months, it’s best to focus your watering on plants that provide the greatest economic and environmental benefit to your homes — trees and shrubs. These plants provide us with shade, clean air, clean water, and increased property values.

In most cases, well-established trees don’t need much supplemental water. However, young trees and shrubs don’t have a root system large enough to obtain sufficient water to survive periods of extreme drought. Consistent water is advised. It’s best to follow a prescription of frequent, consistent and light irrigations — aka the 3-2-1 method .

Mature trees require supplemental water only if normal rainfall is absent from March through July. Watering from August through October is not as important to long-term health. Overwatering is often as bad as a lack of water.

When it isn’t raining between March and July water trees and shrubs in front and backyards once a month with a nice soaking.Trees and shrubs that are in confined spaces, such as between two driveways where the soil is often limited you can water twice a month splitting up the amount of water you would normally use monthly. But remember if you are getting biweekly or monthly soaking with rain you should not have to water. In both circumstances, a slow application is necessary to create a large water profile in the soil. Location is also important. For newly planted trees, apply only to the root ball. For mature trees, target the inside and outside of the drip line.

Water isn’t always the most important factor in tree health.

It also helps to recreate the natural environment with frequent additions of compost and mulch. Compost is thoroughly decomposed organic matter from manures, vegetation or both that resembles rich soil. Compost may be incorporated into the soil. Mulch may be organic (wood chips, pecan shells, pine bark) or inorganic (small rocks, decomposed granite), but generally it’s organic material that has not decomposed.

Mulch is never ever put into the soil, but rather always placed on the surface. If it is incorporated into the soil a nitrogen deficiency will result caused by too much carbon which comes from the mulch, resulting in small, pale green leaves and reduced growth.

Apply a half-inch of compost in the spring and fall, and two inches of mulch in May and September. Cover as much of the root zone as possible to encourage roots to expand and soil to retain moisture.

Treat your trees right and they will treat you right for decades.

Picture of Mark Peterson
Mark Peterson
Mark A. Peterson was a conservation project coordinator for San Antonio Water System before retiring. With over 30 years of experience as an urban forester and arborist, Mark is probably the only person you know who actually prunes trees for fun. When not expounding on the benefits of trees and limited lawns, you're likely to find him hiking San Antonio's wilderness parks or expounding on the virtues of geography and history to his friends.
Dig Deeper

Find expert advice on garden basics, landscape design, watering and year-round maintenance.