Within the last couple of weeks, many homeowners in Central Iowa came under a lawn watering ban. This has some gardeners wondering how they will manage their lawn through summer without irrigation. Thankfully, there is hope, and whether you live in an area with a lawn watering ban or not, many are interested in knowing what they can do to reduce their irrigation needs over summer.
Lawns Can Go Dormant
The cool-season grasses that grow in nearly all Iowa lawns, like Kentucky bluegrass, ryegrass, and fescue, grow best in the spring and fall because they prefer milder temperatures. To keep these lawns green during the hot summer months, irrigation is needed. Without irrigation, the turf turns brown and goes dormant. This is a natural response for these cool-season grasses. While the foliage is dead, the turfgrass crowns and roots remain alive. Most healthy lawns can survive in a dormant state for 4 to 6 weeks without rainfall or irrigation. Healthy lawns allowed to go dormant will green up again with little to no damage when the turf receives sufficient water, either from rain or irrigation.
While dormancy is a natural survival mechanism for cool-season turfgrasses, they cannot remain dormant indefinitely. Cool-season lawns are at risk of dying if dormant for more than 4 to 6 weeks. Thankfully, much of the state has had adequate rains recently, and the turf is still green and growing.
If dry conditions and a watering ban persist well into summer and lawns are brown and dormant longer than six weeks, grass plants could die. Should this happen, new turf can be seeded in early September when temperatures have hopefully cooled and watering is allowed again.
Don't Forget to Raise The Mower
Another critical step to helping the lawn survive summer without irrigation is mowing properly. Raise the mower to cut at a height of 3.5 to 4 inches. The longer grass blades shade and cool the crowns of the turfgrass plants and promote the growth of a more extensive and deeper root system, which is more drought tolerant.
More Summer Lawn Care Tips
There are several other things you can do to help your lawn stay healthy through summer. Learn more in this article: Summer Lawn Care.
Photo credits: 1: west/AdobeStock; 2: Aaron Steil
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