Want better lawn care, Savannah, GA? Start by thinking about irrigation. Water your lawn right and you can expect better grass and less lawn fungus. Water too much or too little, and you can expect trouble.
August is usually Savannah’s wettest month, and often its hottest (click herfer for avg temps and rainfall), so it can be tricky to get the right balance. Here are some tips to help keep your lawn looking its best in August.
Water When Your Lawn Shows Stress from Lack of Water
This may sound counter-intuitive, but experience and science shows that the most efficient way to irrigate your lawn is to wait until the lawn shows signs of stress. If you wait until your lawn looks it needs water, you will almost always take better care of your lawn then if you water routinely. This is especially true in August in Savannah when we already get an average of more than 7″ of rain.
Here are four ways to test if your grass needs water (taken from the Clemson Cooperative Extension Article on Watering Lawns):
- The Color Test:
When your grass needs water it will start to show a bluish-gray color. This is an image of bluish-gray grass from the Kansas State University website. Weather and grass are different up North, but the color bluish-gray is pretty similar:
Note: Bluish-grey is NOT the same thing as brown. You don’t need to wait until your grass turns brown (kind of goes without saying, but I thought I should mention it).
- Leaf Check
When your lawn gets dry it, blades of grass will often wilt, roll or fold over before it begins turning brown and going dormant. When grass starts to bend itself over, it’s time to water. Image below is of fescue starting to wilt and bend (picture from: http://diy.stackexchange.com/questions/6544/why-is-my-tall-fescue-wilting) :
- Screwdriver Test
If it’s difficult to push a screwdriver into your lawn, the soil is very dry. You can use the screwdriver test to confirm what you see visually with the leaf and color test.
How to Water When Your Lawn Shows Drought Stress
If your lawn is showing the above signs apply between 1/2 and 1 inch of water. If it’s done right, water should sink about 5 inches into the soil. If you cannot apply this much water without the water running off the lawn, apply half an inch at a time and let the water soak in before you continue. You can test how deep the water is getting by doing the “screwdriver test” again.
Don’t Water Too Much
Once you water, don’t water again until you see signs of stress again (color, wilting, or “screwdriver test”). You don’t need to water your grass every day unless you are trying to establish newly seeded, sodded, or sprigged lawns. You should aim to add about an inch of water to the root system.
If rain is in the forecast, don’t water.
Calibrate Your Sprinkler
The right sprinkler and calibration makes a big difference. You never want to apply water faster than it can be absorbed. Giving too much water leads to waste. Irrigating too fast can make water run through the grass’s root zone deep into the ground where the grass roots cannot reach it. It’s surprisingly easy to calibrate your sprinkler system. Here’s how:
- Get 5 or more cans with a diameter of 3 to 6 inches. Tuna cans are great. Coffee cans are also good.
- Varies slightly if you are using an “in-ground” or “hose-end” system:
- In ground irrigation system randomly place the containers in one zone at a time. Then repeat the procedure in every zone (irrigation rates may vary by zone).
- Hose-end sprinkler system place the containers in a straight line from teh sprinkler to the edge of the watering pattern. Space the containers evenly.
- Run sprinkler system for 15 minutes
- Collect all cans and pour the water into a single can
- Measure the depth of the water collected
- Calculate the average depth of water by dividing the depth of the water collected in inches by the number of cans
- Multiply the average depth by 4 to determine the applicate rate in inches per hour
A Word About Mowing in Summer
A higher mowing height encourages root growth and reduces heat stress. It’s usually a good idea to raise the mowing height during the summer.