Let Your Grass Go Dormant
It seems that every year we experience a period of drought or heat that adversely affects the grass in our yards. Our regionally adapted grasses are prepared for this onslaught. Grasses have the ability to go dormant for differing lengths of time depending on their genetics and overall health. Dormancy is simply a state of reduced water usage where the plant focuses resources on the roots. The grass will turn brown and is often considered unsightly. If you choose to let grass go dormant during drought here are some tips from The Lawn Institute to help it thrive when better conditions prevail.
Most turfgrass plants can stay in a dormant state for at least 3-4 weeks without the grass dying (longer if the dormancy is induced by cold). If drought goes beyond the 4 week mark it is suggested that water be applied to re-hydrate the grass slightly and keep it alive. Water enough to wet the soil down to 5 inches. This little drink will not green up the grass in many cases but will keep it alive.
Summer dormancy is a perfectly normal response to the stress of heat and drought. It is important to make sure grass is as healthy as possible before dormancy begins and not to stress the grass any more once conditions become unfavorable for growth. Grass should be maintained slightly higher before and during drought. Grass should only be mowed as needed and mowing should be preformed early in the morning or late in the evening with a sharp blade to minimize stress on the turf.
During a dormant phase caused by heat or drought grass should not be excessively fertilized. The dormant turf is not actively bringing in large quantities of nutrients. Excessive fertility before or during a drought can cause injury to the grass.
Some weeds thrive under these reduced water situations because of large tap roots that can hold water. It is best to spot treat these areas with a weed killer or pull the weeds by hand. A broadcast application of herbicide can further stress the dormant turf.
Because the turf is dormant it is not able to readily repair itself. To maintain the best lawn possible keep heavy traffic off of the grass during dormancy.
Keep It Green?
It is possible to keep a lawn green with minimal amounts of water if desired. Lawns need about 1 inch of water per week to stay green, so supplement rainfall with irrigation whenever it is needed. Irrigate every 4-5 days as needed, applying about 0.5-0.75 inch of irrigation water. This can be measured by leaving a tin can or rain gauge on the lawn as you irrigate and measuring the contents after irrigating. Irrigation should be preformed in the early morning to reduce the potential for fungal diseases. Sometimes fertility is needed during the summer months if turf is constantly irrigated. If turf growth decreases or grass begins to loose its color a slow release fertilizer should be applied.