Nature Notes
How can I tell if my lawn needs water?
A "thirsty" lawn turns from the normal green color to a purple-bluish color. In these areas the grass blades will not spring back if you walk across the lawn and your footprints will be visible. This is the first sign of "wilt" and indicates a need for water.
Tips for better watering
- Deep and infrequent watering maintains a healthy root system and reduces weed infestation (as opposed to light and frequent irrigation, which promotes shallow roots and germination of weed seeds).
- Applying one inch of water is often difficult to achieve in a single watering given the slow infiltration rate on most soils. Therefore, smaller amounts of water applied every three to four days may be required to allow water to enter the soil without causing runoff.
- Water is best applied early in the day (5:00 to 10:00 a.m.) when evaporation loss is lowest. Afternoon watering is acceptable but wind may affect uniformity. Night watering minimizes evaporation, but may increase fungal diseases.
- Consider that numerous automatic sprinklers all running during periods of high household use (early morning) may place extreme demands on a community's water system.
- Water the lawn, not driveways, sidewalks, or roads, by adjusting sprinkler heads.
- Mow your grass at the right height during the summer. Longer grass blades increase the depth of the root system, shade the soil, and help drought tolerance (see following table).
Mowing Heights in Inches for Grass to Improve Drought Tolerance
Mowing Heights in Inches |
Grass Variety |
1 to 1.5" |
bermudagrass zoysiagrass |
2 to 2.5" |
centipedegrass |
2.5 to 3" |
tall fescue Kentucky bluegrass perennial ryegrass fineleaf fescues St. Augustine grass |
- If your current grass is not drought tolerant, consider replacing it with one that is.
- Precondition your cool-season lawn for summer by applying fertilizer in the late summer or early fall, avoiding large spring applications of nitrogen-containing fertilizers. This favors root growth and better drought tolerance. Lush, over fertilized lawns require more water.
- Remember that newly sodded or seeded lawns require more frequent watering (for the first three to four weeks) than do well-established lawns, those older than 12 months.
- Keep your mower blade sharp.
- Annual core aeration can loosen compacted soil and allow water to infiltrate deeper into the ground.