Now that summer weather has arrived, many of our customers start asking us about watering the lawn – what is the best time of day to water; how often; how long, etc. Our answers to those questions have changed over the years because of our concern about water conservation practices.
The turfgrasses grown in lawns in Maryland, including Kentucky Bluegrass, Tall Fescue, Perennial Ryegrass, fine fescues and zoysia all have fairly good drought tolerance. Their natural reaction to hot, dry conditions is to going into dormancy until cooler weather and soil moisture returns. However, if you want to keep your grass green during the summer, here is the best advice:
Turfgrasses in Maryland need about an inch of water per week. If your lawn is fairly flat, try heavy, more infrequent watering. Usually an hour or so in each sprinkler location two or three times per week is sufficient. If your lawn is sloped, you will need to do more frequent, lighter watering to avoid the water running off of the slope.
The best time of day to water is very early in the morning if possible. Mid-day and afternoon watering is very inefficient because some water evaporates before it has a chance to get down into the root system. Evening or night watering is more efficient and is acceptable as long as your lawn is not susceptible to fungus diseases, which high humidity and free moisture promote.
You will find if the weather is sunny and hot for an extended period of time, you are going to have a difficult time seeing the effectiveness of your watering because of high evapotranspiration rates. It makes sense to wait until any heatwave breaks and we have a few cloudy days to help make your watering more effective.