Find out how much water your lawn needs and how to deliver it: inches per week, days per week, and how many minutes to run each zone (with cycle-and-soak so it soaks in instead of running off).
About this tool: how long should you water a lawn?Lawn Watering Steps
Set six straight-sided cans around the zone, run it 10 minutes, and pour them into one can. The depth is inches per hour. This plan uses 0.5 in an hour.
Between 4 and 8 a.m. the least is lost to evaporation, and the blades dry off in the day, which limits disease.
One cycle per session is fine on this soil. Water that pools or runs off means the cycles need splitting.
The lawn is the best gauge. Water when it turns grayish-blue or footprints still show an hour later, and wet it about 5 inches deep. If it's soggy, hold off.
Rain counts toward the week. This week's 0 in is already subtracted from the plan. Update it each week.
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Set six straight-sided cans around the zone, run it exactly 10 minutes, then pour them all into one can. Its depth in inches is the zone's rate in inches per hour. Rotors run about 0.25 to 0.75 in/hr and spray heads 1 to 2.5, so a schedule copied from someone else can be far off.
A few deep soakings a week, not a little daily. Aim to wet the top 5 inches. To check, push a shovel in after watering and look at how far down the soil is wet.
4 to 8 a.m. Evening watering leaves blades wet overnight, which invites fungal disease.
A brown lawn is dormant, not dead. Half an inch every two or three weeks keeps the crowns alive. What kills a dormant lawn is watering it just enough to wake it up, over and over.