It’s time to prioritize which plants to save from heat, drought

GARDEN PATCH

Phyllis Webster earned a degree in journalism before embarking on a long career in public relations and marketing. A Granbury resident since 1998, she has been deeply involved in the community. She is an award-winning writer and photographer, as well as a Master Gardener. She has authored Garden Patch since 2001.

Record heat and drought make it a challenge to keep landscape plants healthy. Now, more than ever, we must minimize irrigation to conserve water, a finite resource, that’s needed for drinking, cooking and sanitation. Regardless of whether your utility provider imposes restrictions on water use, it’s time to limit irrigation to keeping high value plants alive.

Most plants only need about an inch of water per week to flourish. However, in extreme heat, evaporation is accelerated, and plants are severely stressed. Normally, patience is key. Many plants adapt to survive drought. Deciduous trees, for instance, drop leaves. In 2022, however, many landscape plants are still recovering from 2021’s record freeze, so expect this double punch to inflict a number of casualties to shrubs, trees, roses and more.

Prioritize by first salvaging plants on your property that will be the most expensive and take the longest to replace. For most homeowners, trees add the most value, and large trees can take decades to grow. Focus your limited water resources on saving trees and shrubs over lawns and annuals. Be more generous with evergreens as they suffer most from leaf loss. Lawns will go dormant, but often bounce back when rain returns. There are no guarantees.

Once daytime temperatures pass 90 degrees with higher nightly temperatures, most plants struggle to complete natural processes, such as photosynthesis. Many perennials, such as iris, simply go dormant. Their foliage dies, but hopefully their underground structures survive. Give perennials a portion of your allocated irrigation budget. This includes ornamental grasses and hardy herbs, such as rosemary.

Use drip irrigation in landscape beds. During extreme heat, overspray on foliage can cause leaf burn. Also, sprinklers that spray into the air waste water — sometimes as much as 60 percent due to evaporation. Drip hoses distribute water directly to root zones where it is needed. Apply 2-3 inches of mulch in planting beds to hold moisture at soil level. Don’t overdo. Too much mulch impedes water filtration and blocks gaseous exchanges.

If you irrigate turfgrass, do so during early morning hours to reduce evaporation and keep water off leaf blades. Many Texas water sources are high in salinity, such as the Brazos River and Lake Granbury. Salt issues are exacerbated during high heat and drought. When lake levels fall, the salt is more concentrated. Plants have various tolerances for salinity. Crape myrtles, for example, fare poorly. Plant leaves are more sensitive to salt than roots, so again, use drip irrigation if possible and avoid recycled water that’s high in dissolved salts.

Do not fertilize plants to encourage growth at this time. Fertilizers contain salts. And plants that put forth new growth may use up vital resources needed for long-term survival.

Finally, plan for the future. Observe which plants fare well this summer and replace poor performers next year. Prioritize for drought tolerance.

For answers to your horticulture questions, please call the Texas AgriLife Extension, Hood County at 817-579-3280 or go online to visit lakegranburymastergardeners.org.

pwebsterco@gmail.com | 817-680-4849