When drought conditions exist, a lawn slows its growth, wilts, then turns straw-colored and becomes dormant. Most cool-season, and some warm-season lawns, will recover again when the drought ends, but they look dead until then. This is a natural reaction by the grass.
Rest assured that most grasses will survive a period of dormancy — the exceptions being Centipedegrass and St. Augustinegrass.
There are several things you should do to help your lawn survive a peroid of drought, and other things you can do so it stays green through a period of limited watering. These same things also will help your lawn survive a period of dormancy.
Fertilize your lawn
Yes, you should continue fertilizing your lawn according to your lawn care program. Contrary to popular belief, it is safe to apply fertilizer during a period of drought or dormancy. In fact, it is more harmful to your grass if you interrupt regular feedings. Therefore, it is important to continue your annual lawn care program whether you are doing it yourself.
Increasing the mowing height on your mower will have several benefits during drought-like conditions. First, the additional height will help the grass blades retain extra moisture and promote deep, healthy roots. Second, the taller grass will aid the retention of moisture in the soil (how to check soil moisture). Remember though, to never remove more than one third of the leaf blade at a single mowing. Also, using a sharp mower blade will help avoid potential fungus that could possibly add more stress to your grass.
Prevent and control weeds
Weeds are more drought-tolerant than grass, and these unsightly looking plants will rob your lawn of vital nutrients and water. You should spot-spray weeds as they appear in your lawn with weed killer for lawns. It will eliminate broadleaf weeds, such as dandelions and clover, without harming the grass. Depending on your grass type, turf builder with crabgrass preventer should be applied to your lawn in the spring. It will provide a regular feeding and prevent weeds and crabgrass from sprouting in the first place.
Water your lawn according to local water restrictions
It is OK to let your lawn go dormant. If you do water your lawn, then be sure always to follow any local watering restrictions during a period of drought. However, in instances where you are permitted to water your lawn, you should do so early in the morning. If you water during the day, then you risk wasting water through evaporation, and watering at night may promote mildew and fungus disease.
You should water deeply to promote strong root growth. If you water sparingly, you will promote shallow root growth that is less drought-tolerant. If possible, your lawn should receive about one inch of water per week, and at the minimum it should receive 1/2″ every two weeks. We recommend that you water in two intervals per week, to allow for deeper penetration and to avoid water runoff.
Monitor the situation
Check with the weather service for local climate and drought information, and pay special attention to local watering restrictions. This should be helpful in tailoring your watering program. You may also want to purchase and use a rain gauge — by knowing how much rain falls, so you can tell how much supplemental water you need. Watering after a light shower can also be an effective way of reducing water loss through evaporation.
Follow-up after the drought
Once the rains have returned the grass should start to green back up — and green up quickly if you’ve continued your regular fertilization schedule. However, there still may be a few brown patches left. If this is the case then you may want to consider raking those spots out and re-seeding. The time between Labor Day and October 1 is an optimal time to repair dead spots in your lawn.
Beware of bugs
Typically, when a mild winter is followed by a dry spring, you will notice a surge in the amount of crawling insects and certain surface lawn insects such as chinch bugs, webworms, and cutworms. You may also see more bugs such as ants and centipedes inside your home — dry conditions send them inside in search of food.