WateringDayShort answer. Water in the early morning — roughly 4 to 10 a.m. — when it is cool and calm, so less water evaporates and the grass dries during the day. Give the lawn about 1 inch of water a week (including rain), in one or two deep waterings rather than a little every day. Avoid evening watering where you can: grass that stays wet overnight is more prone to disease.
Why early morning wins
In the morning the wind is usually calm and temperatures are low, so more of the water reaches the roots instead of evaporating. Texas A&M AgriLife names late evening as the worst time, because the lawn stays wet all night and becomes more susceptible to disease (Texas A&M AgriLife — when and how to water). Purdue puts the ideal window at about 4 to 8 a.m. (Purdue Extension — lawn watering).
How much water a lawn needs
- About 1 inch a week, rain included, during the growing season (Texas A&M AgriLife — when and how to water). Warm-season grasses like bermuda and buffalo often get by on less.
- Deep and infrequent. Wet the soil to around 6 inches, then let it dry out. Daily light watering keeps roots shallow.
- Skip it after rain or when rain is forecast.
The tuna-can test
Put a few shallow cans (tuna cans are perfect) around each sprinkler zone, run the zone for 15 minutes, and measure the water with a ruler. If the cans hold ¼ inch, the zone needs about an hour a week to reach 1 inch — split across your allowed days.
When your city's rules decide the hour
Watering restrictions often ban the middle of the day, and some only allow the night. Use the earliest allowed time before sunrise if you can:
| City | Sprinklers allowed |
|---|---|
| Austin, TX | midnight–10 a.m. or 7 p.m.–midnight |
| San Antonio, TX | 5–10 a.m. and 9 p.m.–midnight |
| Las Vegas, NV | any time Sept–April; not 11 a.m.–7 p.m. in summer |
| Dallas, TX | outside 10 a.m.–6 p.m. from April 1 to October 31; any time Nov–March |
| Fort Worth, TX | outside 10 a.m.–6 p.m. |
| Los Angeles, CA | before 9 a.m. or after 4 p.m. |
| Orlando, FL | before 10 a.m. or after 4 p.m., up to 1 hour per zone |
| Tampa, FL | midnight–4 a.m. or 8 p.m.–midnight, once on your day |
| Hillsborough County, FL | midnight–4 a.m. or 8 p.m.–midnight, once on your day |
In Tampa and Hillsborough County, where sprinklers may only run from 8 p.m. to 4 a.m., start the timer late — 2 or 3 a.m. — so the lawn spends less time wet before morning.
Find your watering day
Never miss your watering day. The WateringDay app reminds you the evening before and alerts you when your utility changes stage or season.