Brown Spot Fungus in Lawns
Image by K. Mathius, University of Maryland

Lawn Browning

Lawn Browning Q&A

By Pat Curran, Horticulture Educator, Tompkins County Cooperative Extension

Question: My lawn has turned brown, but my neighbor's lawn is still green. Why? Should I water my lawn?

Many lawns have turned brown recently. If you look closely, you will see that most have been mowed very short, even "scalped." Most still-green lawns are mowed higher, at the recommended height of 3" (or the highest setting at which your mower can be set). By mowing higher, the grass plants have more leaf surface to feed the roots. This results in stronger root systems, better able to resist drought. Another benefit of mowing higher is fewer weeds, especially annual weeds like crabgrass, which germinate in the thin areas of stressed lawns. Taller grass is also more resilient to foot traffic.

Some local businesses do keep their lawns both short and green by watering them with sprinklers, but sprinklers waste up to half the water through evaporation. I do not encourage homeowners to use sprinklers on their lawns, because I think it is more important to water valuable landscape plants, such as recently planted trees and shrubs, preferably with a soaker hose or bucket. By 'recently planted,' I include even last year. I planted many small trees and shrubs last September, and they receive an occasional deep drink.

A brown lawn is usually not dead, just dormant. Dormancy is a life-saving response to hot dry weather. It would take several more weeks of drought for the lawn to actually start dying. This is unlikely in upstate NY, although this year's unusual weather makes predictions difficult.

If parts of your lawn do die, the best time to seed a new lawn is late August through September. This allows time for the grass to get well established before winter. Our cool season grass species grow strong roots in cooler fall weather than they would in a spring seeding, but they need enough time to do so. It also means less watering for you, the homeowner, until the seed germinates.

Before seeding or re-seeding a lawn, do some research to figure out which grass seed to purchase. There are 4 species of grass adapted to our area. One is more tolerant of light shade (no grass will grow in heavy shade), and another is more drought-tolerant. There are also varieties of each species. The best choice is a mix of species or a blend of varieties. The best choice may also vary in different parts of the lawn. The highest maintenance lawn grass for our area is Kentucky bluegrass, so stay away from a pure bluegrass lawn if your goal is lower maintenance.

Have you seen those magazine ads for zoysia grass? Yes, it is tough and drought-tolerant, but the ads never mention its big drawback for our area: it turns brown at the first frost and doesn't green up again until May. Most people around here want green lawns in spring and fall, even if they have to mow. But perhaps zoysia has a place for the snowbirds' summer lake cottage.

For more information on lawn care, including lawn browning, consult the Cornell gardening website, fruit section, or call the horticultural hotline at Cornell Cooperative Extension of Tompkins County at 272-2292.

Last updated January 29, 2021