Keeping Your Kentucky Bluegrass Turf Green All Summer
submitted by Don Janssen, Extension Educator
To keep a lawn green throughout the summer it needs to be watered.
Most Kentucky bluegrass turf grasses will go dormant during hot summer weather if they are not watered. During this dormant period the grass will turn brown but once it is adequately watered, it greens up and begins growing again. To keep a lawn green throughout the summer it needs to be watered.
Homeowners wanting a cool season lawn green through the summer usually ask three questions; How much water should I use?, How often should I water?, and When should I water? Here are the answers for many lawns.
The amount of water to apply greatly depends on the soil type. To wet the soil in the root zone of the grass plant, water needs to reach a depth of 5 inches. If the soil is initially very dry, 1-1 1/2 inches of water may be needed to wet a clayey soil down that far.
To determine how long it takes a sprinkler to apply an inch of water, put cans at different spots in the sprinkler pattern. Turn on the water and keep track of the time it takes the sprinkler to put an inch of water in the cans.
Do not allow water to run off the surface or to form puddles. If you notice water running off the turf area but you still need to apply more water, turn the water off for 30 minutes, then resume watering until the desired amount has been added.
How often to water is affected by grass species, soil texture, climate, exposure, and intensity of use. Ideally, the grass plants should dictate the watering program. Light wilting, a color change to a more greyish or bluish-green shade, or footprinting (when plants will not rebound after walking on them) are indications that irrigation is necessary.
Keep the interval between waterings as long as possible without allowing the plants to go into water stress. Some areas of the lawn will probably dry faster than the rest. This is common on southern exposures, sunny areas, borders of sidewalks, and slopes.
The most efficient time to water lawns is early in the morning from 4 to 10 a.m. Less water is lost to evaporation due to lower temperatures and less sunlight. Also, wind velocities are usually lower.
Watering in the evening should be avoided. If the grass plants go into the night-time hours wet, they will remain wet for more than six hours. This wet foliage will favor the growth and development of turfgrass diseases.
University of Nebraska-Lincoln Extension in Lancaster County is your on-line yard and garden educational resource. The information on this Web site is valid for residents of southeastern Nebraska. It may or may not apply in your area. If you live outside southeastern Nebraska, visit your local Extension office