Watering for Established Turf - Deep and Infrequent
A Northern Virginia Lawn needs 1 inch of water per week.
This can be from rain, or sprinklers, or a combination of both. Deep infrequent watering is better than daily light sprinkling. Your lawn needs a minimum of 1 inch of water weekly. To determine the soil moisture depth, use a screwdriver or a garden trowel. Push it into the soil and if you meet little resistance, then the soil is wet. If it does not push easily into the soil, then additional water will be needed.
When should I water?
The best watering time is early morning when there is less evaporation. If lawn shows symptoms of severe drought (i.e. color loss/ visible foot prints) water regardless of time of day.
Test the sprinklers.
To see how much water is being put out by your sprinklers, test your system during the time of day you would normally water. Because of their straight edges, cat food or tuna cans work well in collecting the water. Put the cans out in the different zones (areas) and run the system through its normal cycle. Measure the water in each of the cans to see how much has been caught (different zones/ outdoor bibs can produce different levels). Water pressure can vary during the day because of community use.
If 1/3 inch is caught in 30 minutes than the system needs to be run 3 times a week for 30 minutes to get the desired inch. If the system puts out ¼ inch in 30 minutes you would want to increase the time to get the 1/3 inch needed. This test will also let you know if you are overwatering, which can promote disease.
Keep in mind that a very sunny lawn will have the water evaporate more quickly so an extra watering may be needed when we have those stretches of high heat in the summer.
Summer Dormancy –
Dormancy is one of the mechanisms that help plants survive stressful conditions. Summer dormancy occurs in a lawn when grasses are exposed to an extended period of heat without adequate moisture. Summer stress may cause a lawn to stop growing, thin out and loose color.
A lawn going severely dormant during extended drought periods may have portions brown out to the point they do not recover when the milder fall temperatures and rains return. Proper lawn care promotes recovery by feeding the grass and pushing back the weeds that may have tried to encroach during the stressful summer heat.
Watering for New Seeding
New seed needs daily watering to keep it from drying out and disrupting the germination process.
Once watered in, the seed needs to be kept moist or it will dry out and stop germinating. The first watering needs to be 15 – 20 minutes to “water the seed in”. As soon as it is watered in, the seed gets sticky and begins to soften starting the germination process. To help keep the seed moist it will need to be lightly watered daily 5 – 7 minutes (heavy waterings could water log the seed and stop germination).
If we have hot or windy days (or there is a very sunny area) the seed will need to be lightly watering more often (at least 2 times daily). Because bare/thin or dead brown spots do not have the advantage of shade from established grass, those areas will also need to be watered more frequently to keep the seed germinating. Remember these are light waterings (5-7 minutes in each area).
Once the seedlings are established ( 1 to 1 ½ inches high) go back to the deep infrequent watering for an established lawn.