Why Does Grass Turn Brown in Winter?

Depending on the type of grass planted in your lawn and the area you live in, it’s not unusual for your lawn to turn brown during winter. Assuming there is no lawn disease, damage from de-icing salts or heavy foot traffic, your grass has just gone dormant and will green up again when warmer temps and rain arrive in spring. If your grass is brown in summer, it should green up again when high heat moderates and rain returns to normal levels.

When weather is extremely dry or temperatures are extremely hot or cold, your grass becomes dormant and brown. But not dead. There’s no need to worry, it’s just the plant’s natural response to unfavorable conditions. While the leaves of the grass are brown, the crown deep inside the plant is very much alive. As with any plant under stress, it’s conserving resources until conditions improve. Once conditions are favorable again – rain returns or temperatures moderate – the turf should become green within 10-14 days without you lifting a finger.

How long and when your grass goes brown in winter depends on the species and variety you planted. In the mid-Atlantic, New England, Great Lakes area, and other temperate areas, you should have cool-season grasses planted in your lawn. Many species of cool-season grasses go dormant when freezing temps arrive. If you live in the Southeast, Southwest, and other hot or arid areas, you should have warm-season grasses planted in your lawn. These species become dormant during very dry conditions and cold temperatures below 55 Fahrenheit but will green up again when rain arrives.

Reasons your grass may be brown

• Damage from de-icing (usually occurs along sidewalks and driveways)
• Heavy foot traffic or play areas (soil compaction)
• “Fertilization” or digging from dogs
• Dormancy from winter or summer temperatures
• Competition from trees and shade
• Disease or insect damage
• Winter injury or winter kill
• Overapplication of fertilizer
• Lack of water (drought)
• Acid or alkaline soil (improper pH levels)
• Incorrect grass species for your area
• Unnecessary liming
• Mowing grass too short
• Thatch

Is your brown lawn dormant or diseased?

Generally speaking, dormancy affects your entire lawn and disease affects isolated areas of your lawn. If you believe your lawn might be diseased, search your local university extension for common diseases of grasses in your region.

How do you know what type of grass is planted in your lawn?

That’s tough to determine unless you’re an expert on grasses – there are dozens of species within each of the types of grasses listed below. If you seeded your own lawn and bought that seed at a local garden center, you probably have an appropriate species for your area. If you bought seed online, without knowing what type of grass was appropriate for your area, you may have planted a cool-season grass when you need a warm-season grass or vice versa. Pennington has an excellent resource with images on types of turfgrass for the entire U.S. You can also search your local university extension (link above) to identify the best types of lawn grasses for your region.

Annual and Perennial Ryegrass

Annual Ryegrass is a cool-season grass for sunny areas. It is coarse-textured and shiny light green and thrives during the cooler months. Annual Ryegrass has low heat tolerance and dies in late spring to early summer. It is frequently added to cool-season lawn seed mixes to help establish a lawn quickly.

Perennial Ryegrass is a cool-season grass for sunny or partially shaded areas in regions with mild winters and cool moist summers. It is moderately dark green in color with good density and fine leaf texture. Perennial Ryegrass produces attractive, tough leaves and low growing crowns that create a stable turf with a bunchgrass-type growth habit. It grows best during cool temperatures and is very competitive, establishing quickly. Fall seeding is recommended. Drought tolerance in Perennial Ryegrass is good but it may go dormant during dry periods until rain returns. It is frequently included in lawn seed mixes with Kentucky Bluegrass and Fine Fescue to make a hardier turf. Suitable for moderate foot traffic areas and for play areas.

Tall Fescue

Tall Fescue is a cool-season grass for sunny or partially shady areas. It is a coarse-textured grass with medium to dark green color and moderate density, but some cultivars have a finer texture. Tall Fescue has good disease resistance and excellent tolerance to heat stress. It is a bunch-type grass with a more extensive root system than any other cool-season turfgrass. Because of its extensive roots, it has good heat tolerance and drought resistance and grows in a wide number of zones, but it is less cold hardy than most cool-season grasses. During drought or periods of high heat with little water, it can go into summer dormancy, turning brown. Upon return of moisture, it will green up again. Very good transition zone grass – adapted to moderately cold winters and warm summers. Suitable for moderate recreation and foot traffic areas with good initial wear recovery, especially in spring and fall when growth is rapid.

Fine Fescues

Fine Fescues are cool-season grasses for shady areas, but they like a little sun. They are the best cool-season grasses for dry, shady lawns and create a dense, wear-resistant turf when well established. Fine Fescues have a deep green color, an upright or clumped growth habit, and a very fine texture with narrow leaf blades. Fescues tolerate hot and cold weather, have good winter hardiness and can be used in areas that are subject to wide temperature fluctuations. They are well adapted to cool summers and high altitudes and can do well even in cold and arid climates. Fescues have very good drought tolerance for a cool-season grass but can go dormant in summer if rainfall is sparse. When rain returns, they green up again quickly. Several species of fine fescues are used in grass seed mixes: Creeping Red Fescue (Festuca rubra), Chewings Fescue (F. rubra commutata), and Hard Fescue (Festuca longifolia). They are usually mixed with other turf species because the seed germinates rapidly, the grass establishes quickly, it tolerates shade, and fills in shady areas. Hard fescue, as well as red fescue, can be left unmowed as ornamental ground covers or on slopes and other hard-to-mow areas. Fine Fescues have moderate wear resistance and make an ideal play surface but do not recover well from severe injury.

Bermudagrass

Common Bermudagrass (also Bermuda Grass) is a drought-resistant, warm-season grass for sunny areas only. It is the best grass for hot, dry or tropical climates. It is a medium, coarse-textured grass with a gray-green color. Common Bermudagrass has excellent heat tolerance up to 110 Fahrenheit but has a winter dormancy period, turning tan or brown when temperatures drop below 55 Fahrenheit. Bermudagrass is highly drought-resistant, but can go into summer dormancy when rainfall is low but it greens up again when rain returns. Bermudagrass establishes a deep root system and produces long rhizomes and stolons, but tends to produce thatch. Bermudagrass withstands wear better than most grasses and can tolerate heavy foot traffic, making it ideal for homes with children and pets.

St. Augustine Grass

St. Augustine Grass is a drought-tolerant, warm-season grass for sunny areas or moderate shade, but varieties have a wide range of shade tolerance. It is a coarse-textured, robust, fast-growing grass, light to medium green in color, that establishes rapidly with a creeping growth habit. It is a popular choice in coastal regions with hot, tropical climates as it can withstand extremely saline conditions. St. Augustine Grass is propagated by stolons and forms a dense, prostrate turf that is virtually weed-free, but thatch is a problem. It thrives in heat up to 105 Fahrenheit, but has poor tolerance to low temperatures – it goes dormant and turns a tan color in winter when temperatures drop below 55 Fahrenheit. In periods of low to no rainfall in summer it may also become dormant but will green up again when rain returns. Moderate wear resistance.

Zoysia Grass

Zoysia Grass is a warm-season, drought-resistant grass for sunny areas in hot, humid, and tropical climates. It is tolerant of some shade, depending on the variety. Zoysia is attractive, uniform, dense, low-growing, medium textured, and light to dark green in color. Its leaf texture is fine to medium coarse, forming a dense, low maintenance lawn that spreads by stolons and rhizomes, although it is slow to establish. Zoysia tolerates heat exceptionally well up to 100 Fahrenheit but is subject to winter dormancy and turns tan to brown when temperatures drop below 55 Fahrenheit. The deep roots of Zoysia require infrequent rain, making it an excellent choice for drought-prone areas. It will remain green during short periods of drought but may go into summer dormancy if rainfall is absent for long periods, but it greens up quickly when rain returns. Zoysia has superior wear resistance and tolerates heavy foot traffic.

Centipede Grass

Centipede grass is a warm-season grass for sunny areas in hot, humid and tropical climates where rainfall is high and summers are warm and humid. It produces a dense, medium to dark green turf with a medium to coarse textured grass blade which creates an attractive, very low maintenance lawn. Some varieties are adapted to shade and are tolerant of pine tree shade. Centipede grass is tolerant of high temperatures up to 100 Fahrenheit but goes dormant in winter when temperatures drop below 55 Fahrenheit. Centipede grass only has moderate drought resistance and goes into summer dormancy if rainfall is absent for too long, but has a rapid recovery rate. Centipede grass has poor wear resistance and recovers slowly from damage.

Bahia Grass

Bahia grass (also Bahiagrass) is a warm-season, drought-tolerant and heat-tolerant grass for sunny areas that is only planted in the heat and humidity-prone deep south and Gulf Coast U.S. Bahia grass grows by spreading rhizomes and produces a relatively durable, low-growing, low-maintenance lawn that is light green in color with coarse-textured grass. Bahia has low water requirements and does best in sandy, acidic soils. It is valued for its ability to thrive where other lawn grasses falter but its open growth habit often invites lawn weeds.

Sources: University of California, The Lawn Institute, Missouri Botanical Garden.