Guide to Watering your Lawn
How Much and When to Water Your Lawn
Summer time means outdoor fun. A lot of us have happy memories of running under the lawn sprinkler as kids. Sprinklers always seemed to be running. If you didn’t have one in your backyard, it was a sure bet that several neighbors did. The lawn sprinkler was as much a part of summer as backyard barbecues and lemonade, but things are changing. As we realize that water is a precious resource, many property owners are changing their habits and finding new ways to maintain their lawns with less water.
Around 80% of residential summer water usage is used outside. Lawn maintenance uses more water then home gardens or swimming pools.(1) As urban populations grow the demand for water increases and many municipalities enact watering restrictions during dry seasons. Sometimes total outside watering bans are needed, other times alternate day or weekly watering schedules are enacted.
More and more people are looking for ways to conserve water and still maintain their lawns. Let’s take a closer look at when we should water our lawns, how often we should water our lawns, and just how much water is really needed to water our lawns.
When to water the lawn
There are certain times when watering your lawn is necessary. New lawns need water. If you have newly seeded your lawn or planted new sod, you will need to supplement Mother Nature if the times are dry. It’s important to keep the soil moist so new seeds can take root and the root system in new sod can take hold. One way to reduce the need to water new lawns, is to plant them during the rainy season. Spring and fall are the best time to spread grass seed and plant new lawns. However, during the first year, a new lawn needs a little extra care and a little extra water.
You’ll also need to water if your lawn develops summer patch disease. Summer patch is most destructive to Kentucky bluegrass and creeping red fescue lawns. Choosing grass varieties that are not prone to this disease is the best way to avoid it. Summer patch is caused by a fungus and appears as wilted, dark-green, and then straw-brown circular areas. At first the patches are only 1-2” in diameter but they will increase in size. The fungus thrives in hot, dry conditions. Watering the affected area so the soil is wet 3” deep is necessary to treat the disease.(2)
How often to water the lawn?
The best way to conserve water during the summer is to allow your established lawn to go dormant in hot weather. Grass naturally goes into a dormant state during drought conditions. Although some varieties of grass are drought tolerant, even these types of grass will eventually go dormant during hot or dry conditions if rain or irrigation does not occur. During the dormant period upper grass blades will turn brown but the lower part of the plant will stay alive. Grass needs only about 1” of water every 3 weeks when it is dormant. If you let the grass go brown and then you overwater, you’ll drain food reserves. (3)
If you decide to water regularly during the summer, don’t overwater. Flooding the grass or watering too often can reduce root growth. Wait until foot prints remain in the grass, then water. Try to water evenly. If you’re unsure of which areas are receiving the most water, put tin cans randomly on your lawn. After you’re finished watering, check water levels in the cans to see which spots get the most and the least water.
The best time to water the lawn?
Water the lawn in the morning. Water evaporates quickly during the midday hours and night watering can promote diseases and increase insect growth. Keep your lawn healthy during hot dry periods by limiting foot traffic and setting the lawn mower blade on high.
Check out other ways to save water in the xerescaping overview and related articles. Every year we become more conscious about water conservation. Learning ways to reduce water consumption by watering our lawns less and more efficiently will go a long way in saving our precious water supplies.
1 Home Lawn Watering Guide. Retrieved May 18, 2010. University of Missouri Extension: http://extension.missouri.edu/publications/DisplayPub.aspx?P=G6720
2 Dernoeden, Peter. Summer Patch Disease of Lawn Grasses. Retrieved May 12, 2010. University of Mayland: http://www.hgic.umd.edu/content/documents/TT-18.pdf
3 Water Lawns the Right Way. Retrieved May 18, 2010. University of Illinois Extension: http://urbanext.illinois.edu/lawnchallenge/lesson4.html