If you have noticed on your ornamentals, especially hydrangeas and roses, that the tips of the leaves and portions of leaves look scorched, you are seeing the results of drought stress. The plant roots cannot take in enough water fast enough in order to satisfy the needs of the leaves and so those portions die.
This year it seems that we go from one extreme to another when we consider rainfall. We had a very wet spring and now we are experiencing a very dry summer. The limiting factor in our landscapes and gardens tends to be the amount of precipitation that we receive. So how do we deal with drought?
Most folks resort to some form of irrigation. Drip irrigation is the most efficient in gardens. On hot, dry days, overhead irrigation or sprinkler irrigation results in less than 30 percent of the water hitting the soil.
Timing is also important. Irrigating at night promotes disease because the fungi and disease organisms prefer moist environments. Providing irrigation early in the morning allows the plants to dry off.
Providing mulch around plants prevents more rapid evaporation from the soil and keeps the soil moist longer. Aerating the lawn allows the water to penetrate deeper into the soil rather than running off. It also helps to break up compaction and allows the roots to pursue moister soil.
If your irrigation water is running off or over the curb you are either providing too much water and the soil is saturated or the soil is compacted a few inches down and has nowhere to go.
A good rule of thumb is that most plants and lawns prefer about 1 inch of water per week, and in dry conditions 1.5 inches per week. It’s better to water once per week rather than several times, and let it soak to the root zone. Irrigating less the 1 inch promotes shallow roots and less resistant plants to drought.
How do you know how much water you are using? Place pie pans in the arc of the spray and set the timer.
If there is 1 inch, you’re doing fine. If not enough, lengthen the time, and too much, shorten the time. Remember that one to 1.5 inches per week of water is sufficient. One deep watering is better than several shallow waterings.
The lawn needs watering when it turns from green to a bluish-gray to almost white. If you leave footprints as you walk across the grass, it’s another sign. The low water level in the leaves prevent the grass from springing back. Grass plants in general respond to drought stress by rolling their leaves. Other plants may fold over or wilt.
A screwdriver can test how dry or moist the soil may be. If the soil is dry, pushing the screwdriver into the soil will be difficult. Moist soil will allow the screwdriver to penetrate deeper. Check after watering to see the depth.
Be careful about adding too much potting soil when amending the soil when planting ornamentals. Some potting soils work great in small pots but may provide a barrier to water moving down into the soil. Don’t be afraid to use a trowel around plants to check to see how moist the soil is. Go down at least six inches. Get into the root zone.
Vegetable gardens require vigilance to prevent damage during the drought periods. Irrigating 1.5 inches per week and deep irrigation is best. Mulch around the plants also slow the evaporation process.
Upcoming Master Gardener program
Troup County Extension is hosting the Master Gardener Extension Volunteer Program starting Aug. 9. If you wish to hone your skills in horticulture and related subjects this might be the program for you.
We have a variety of topics lined up and taught by excellent instructors. We will cover a wide range of topics: botany, entomology, soils, plant nutrition, insect control, vegetables, herbs, plant propagation, planting and maintaining ornamentals, troubleshooting, pollinators, turf, trees and much more.
If you have your Tuesdays and Thursdays available and are willing to help out UGA Extension, send an email or call the office for more information. Please apply as soon as possible. We need at least 10 to sign up.
What’s going on in Extension?
Master Gardener Extension Volunteer class will begin Aug. 9 and run through Oct. 20. Classes will be held Tuesday and Thursday afternoons. The cost is $150. Call or stop by the office an application.
Georgia Master Cattleman Program starting Sept. 6. Call for more information.
Market on Main: Every Saturday morning from 8 a.m. to 10 p.m. starting June 4. Come by and enjoy the pick of the day. Carmike Cinemas LaGrange 10 parking lot.
If you have any questions or concerns, stop by or call the Extension office.
Brian Maddy is the ANR Agent for Troup County Extension. The Troup County Extension office is located at 114 Church St. in LaGrange and may be reached at 706-883-1675, Monday–Friday 8 a.m.–noon and 1–5 p.m.