The Best Time to Water Your Grass (It's Earlier Than You Think)
Watering at the wrong time wastes money and invites lawn disease. Here's the sweet spot that gives you a greener lawn for less.
Why morning wins
Between 4 a.m. and 9 a.m., the air is cool, wind is usually low, and the sun isn't yet baking the soil. Water soaks straight into the root zone instead of evaporating off the leaf surface.
By the time temperatures rise, the grass blades have dried — which is critical for preventing the fungal diseases that thrive on wet leaves.
How much water your lawn actually needs
The universal rule: 1 inch of water per week, including rainfall. In 90°F summer heat, bump it to 1.5 inches.
Place an empty tuna can on the lawn and run the sprinkler for 15 minutes. Measure the depth, then math out how long it takes to hit 1 inch. That's your weekly run time, split into 1–2 sessions.
Frequently asked
How long should I water my lawn?+
Long enough to deliver about 1 inch of water per week, split across 1–2 sessions. For most rotor sprinklers that's 30–45 minutes per zone, twice a week.
Is watering at night bad?+
Yes. Wet blades overnight create the perfect environment for fungal diseases like dollar spot, brown patch, and pythium.
Can I water in the middle of the day?+
You can, but you'll lose 30%+ to evaporation. It won't burn the grass (that's a myth) but it's wasteful.