Should you Water in Winter?
Dormant grass is not dead grass. It’s grass that is resting. When grass goes dormant, it’s considered to be a period of rest, especially during a time of stress. Grass becomes stressed by several factors, including drought, cold temperatures, and a lack of moisture in the soil.
Dormancy is a naturally occurring event that allows grass to conserve water and nutrients. Most lawns will go dormant during the fall and remain dormant until the spring. Once the weather warms and watering or rain begins again, the grass will recover if the drought has not been too severe. Recovery may take up to three months to occur.
Should we water our lawn in winter?
Though the grass is dormant, the roots are growing slightly. Some water is a good thing to ensure a healthy return in spring. Rainfall is usually enough to keep a lawn healthy, but that could be sparse when your area is in a drought.
John Dromgoole, the Weekend Gardner, says, “Most of the time, we don’t need to water in winter, but if things are really dry, once a month should take care of it.”
According to Texas A&M AgriLife Extension, you can keep your lawn in good condition even when water conservation is needed. Depending on your area and the water rationing policy your local government adopts, it is possible to maintain a healthy, dormant lawn while in a drought.
It is better for the overall health of a lawn to water infrequently in drought conditions, but deep enough to wet the soil to the recommended depth. This reduces disease, helps air to move to the plant roots, and conserves water.
For deep watering, you should apply enough water to wet the soil to a depth of 6 inches. Use the following steps to determine how long to water.
- Set five or six open-top cans randomly on the lawn (cans with short sides, such as tuna or cat food cans, work best).
- Turn the sprinkler or system on for 30 minutes.
- Measure and record the depth of water caught in each individual can.
- Calculate the average depth of water from all the cans. For example, you have used five cans in your yard. The depths of water collected in the cans were as follows: 0.5 inch, 0.4 inch, 0.6 inch, 0.4 inch, and 0.6 inches. Add the depths together and then divide by the number of cans you used (five in this case). 0.5 inch + 0.4 inch + 0.6 inch + 0.4 inch + 0.6 inch = 2.5 inches ÷ 5 cans = 0.5 inch of water in 30 minutes
- Use a garden spade or a soil probe to determine how deeply the soil was wet during the 30 minutes. Push the probe into the soil. It will push through wet soil easily but less easily when it reaches dry soil. Measure the depth of the wet soil.
- In some areas of Texas, the depth of topsoil in the lawn may be less than 6 inches. If soil is less than the desired 6-inch depth, then apply only enough supplemental water to wet the existing soil profile
Knowing how much water was applied in the 30-minute cycle and how deep that volume of water wet the soil, you can then determine how long the sprinkler must run to wet the soil to a depth of 6 inches.
Though lawns in the Brazos River basin are now experiencing winter dormancy, they may have also been suffering from drought stress before the winter months. With about 91 percent of the Brazos River basin currently under some form of drought conditions, it’s likely that as winter dormancy eases, drought dormancy could remain. Water conservation has been a priority since the BRA Water Supply Reservoirs went under a Stage 1 Drought Watch, with one reservoir under Stage 3 Drought Warning.
Stage 1 Drought Watch asks for a 5% voluntary reduction in water use, while Stage 3 asks for a 20% reduction in water use. What does that mean for your dormant lawn?
Symptoms of drought stress include grass leaves turning a dull, bluish color; leaf blades rolling or folding; and footprints that remain in the grass after you walk across the lawn. Although drought symptoms generally will develop in 5 to 7 days, symptoms may occur in as little as three days or not for 15 days. Therefore, under Stage I reductions, your grass quality should not suffer.
Run-off can be a serious problem that wastes large amounts of water. Soil type and the application rate of the sprinkler system determine how quickly run-off will occur. If water is applied faster than it can seep into the soil, it can run off the lawn and be lost.
To Prevent Run-off:
- Monitor the lawn for several irrigation cycles to spot water running onto sidewalks, streets, or gutters.
- Note how long the sprinkler ran before the water began to run off. Stop watering at that point to prevent water losses from run-off.
- Allow the soil surface to dry (30 minutes to 1 hour).
- Change your irrigation timer to the shorter time limit noted above and begin watering again.
- Continue this cycle until enough water has been applied to wet the soil 6 inches deep.
Irrigation during Stage III becomes more difficult. You still need to water deeply to maintain a healthy root system. However, it is time-consuming to hand-water the lawn to the depth needed.
Some watering options during Stage III of water rationing include:
- Water with a hose only in those areas that are showing severe drought stress. Make sure that enough water is applied to effectively wet the soil. When puddling or run-off begins, stop watering that area, let the surface dry and then resume watering. Continue this cycle until the soil is wet to the appropriate depth. Use a sharp probe or spade to help determine the depth of water penetration. Do not water those areas again until drought stress symptoms reappear. This requires considerable time and daily attention.
- If you do not have the time to hand-water or the yard is too large, you may want to stop watering the lawn altogether. Most warm-season turfgrass species can survive short periods of drought stress. When the grass is under severe drought stress, it may go dormant.
It is helpful to understand the strengths and weaknesses of your grass. If the grass in your lawn goes dormant during drought, you could stop watering altogether.
Texas A&M AgriLife Extension’s rating for drought tolerance of turfgrasses used in home lawns:
- Buffalo grass: high level of tolerance, goes dormant and recovers well from drought stress.
- Bermuda grass: medium-high level of tolerance, goes dormant and recovers well from drought stress.
- Zoysiagrass: low-high level of tolerance; Zoysia japonica varieties such as Crowne and JaMur Palisade have high drought tolerance, while varieties like Meyer have poor drought tolerance. Most Zoysia matrella varieties such as Cavalier and Zeon, have poor to medium drought tolerance.
- St. Augustine grass: medium level of tolerance, moderate drought resistance from an extensive, deep root system but poor ability to go dormant. Significant turfgrass loss during long drought periods.
- Centipede grass: medium level of tolerance, moderate drought resistance from an extensive, deep root system but poor ability to go dormant. Significant turfgrass loss during long drought periods.
- Tall fescue: low-high level of tolerance, drought tolerance is low to medium
Grass can go up to six weeks without water, depending on the condition of the lawn, soil, and other environmental factors. Always follow the water restrictions in your area to conserve the water that is necessary for daily living.