Ideally, your lawn needs to be watered when it needs water. A set schedule may be easiest for most of us, but sometimes just doesn’t fit the needs of the grass. Likewise, while we can recommend what works for most lawns, it may not work for all.
Signs that your grass needs water are wilting, a bluish-grey appearance, or “footprints” left when you walk through your lawn. Grass wilts when the loss of water from the plant (evaporation through the leaf, called transpiration) exceeds that taken up from the root system. (Kind of like us--when we're out in the heat and sweat a lot, we need water or we'll definitely wilt!)
The type of soil in your lawn affects your lawn’s watering needs. Coarse, sandy soil absorbs water faster, but retains less water than fine soil like loam and clay. It will take less water to reach a 6” depth in sandy soil, but you will need to water more often. On the other hand, a heavy clay soil will absorb water slowly, and you want to be careful that you don’t have water running down the street. You may have to water twice in one day to reach the 6” depth.
Water pressure is an important factor, which is why we recommend using tuna cans above to actually measure how long it takes to accumulate an inch of water. Water pressure can vary from house to house.
Cultural practices on your lawn, like mowing and fertilization, will also affect watering needs. A lush, vigorously-growing lawn will actually use more water than a poorly performing lawn.
Windy weather will dry out your soil and your lawn. In periods of high wind, you may need to increase your watering.
If your lawn is sloped, you will need to water the top of the hill much more than the bottom.
If you have fescue, rye or other cool-season grass, you may follow the same guidelines outlined here, but you may also have to water lightly every day if temperatures are in the nineties or above. “Shade” grass is not really sun intolerant—it is heat intolerant. A fescue lawn in full sun will do fine in moderate temperatures. During the hot summer, when temperatures soar, a daily light watering early to mid-afternoon will help cool off the grass. You will still need to do your deep watering twice per week or more frequently if you notice it wilting between waterings
If you have newly-seeded grass, you will need to keep it moist throughout the germination period. Water it lightly just to a depth of about 1”. Do not overwater or your seed will wash away or clump up in puddles. If the seeded area is bare, you may want to lightly cover it with grass clippings until it germinates. If it dries out, it will die.
If you have newly-sodded grass, water lightly twice per day until it is rooted down.
Be sure your lawn has good drainage. If you frequently have standing water, you may need to aerate your lawn (an application of Sup-R-Soil in the spring may help,) or in severe cases, consider digging swales or putting in a French drain system, or bringing in topsoil to raise the lawn higher.
What if you can’t water? During the summer, your water bill may get too large, or we may have periods of water-rationing during drought, or maybe you just can’t get out and water. Bermuda lawns may begin to go dormant. This is the grass’ protective strategy. It will prematurely turn brown and go into drought-induced dormancy. It’s not dead, it’s just resting in sleep-mode. When the fall rains come, it should green back up again. This isn’t the healthiest thing for the grass, but it will usually survive just fine. Fertilization, even when it’s brown (the root system is still active,) will help it to be healthier when the fall rains come. If you have a fescue or bluegrass lawn, it MUST have water, or you will lose most of it.
If you have to cut back on watering, leave your lawn a little higher than normal, rather than mowing it short, to help it cope with the heat stress.
What about that high water bill in the summer?Almost every municipality charges for water and sewage usage based on the amount of water you use. Often, our members use more water outside the home than inside...but you are still charged for sewage based on your 'outside the home' water use, even if this water never enters the sewer lines. If you fall into this category, consider installing a second water meter for outside water use only. After a one time installation fee, you should see a significant decrease in your water bills. You will need to contact your city for details.
Your lawn tech or anyone in our office would be happy to help if you have any questions about watering!