Watering deeply in a heatwave
Drought or heat stress: water deeply early in the morning to cool the roots. A single deep soak beats frequent shallow watering.
- When
- When the problem shows up
- For
- Any lawn
- Rule
- wx-emergency-water · Turgeon; Regional
Drought or heat stress detected — water deeply early morning to cool roots and prevent dormancy. A single deep soak (30–40 min) beats frequent shallow watering.
Why a deep soak
In a heatwave the top few centimeters of soil dry and heat up fast. Light daily watering only wets that hot layer, keeps the roots up in it, and much of it evaporates by noon. One deep soak gets water down to where the roots can draw on it for days and keeps the root zone cooler.
How
- Water early in the morning, before about 7 a.m.
- Run the sprinkler long enough to deliver about 2–2.5 cm (¾–1 in). For many sprinklers that is 30–40 minutes; check with a can on the lawn.
- On clay or slopes, split it into two runs half an hour apart so it soaks in.
- Repeat every two to four days while the heat lasts, rather than daily.
Also during a heatwave
- Raise the mower and mow less often; see summer mowing height.
- Do not feed or apply weedkiller.
- Keep off the lawn as much as possible.
If watering is restricted, it is fine to let a cool-season lawn go dormant and brown. It usually recovers when rain returns.
Sources
- A.J. Turgeon — Turfgrass Managementturgeon
- Regional practice — continental climate, zone 7regional