Grass dormancy is a natural survival mechanism for turf, causing a temporary cessation of growth and a loss of green color. This process allows the plant to conserve energy and moisture, protecting the root system from environmental stressors. Texas lawns are predominantly composed of warm-season grasses, such as Bermuda, St. Augustine, and Zoysia, which are genetically programmed to enter this resting phase annually. Understanding this cycle is important for homeowners to ensure the long-term health of their turf.
Environmental Triggers for Grass Dormancy
The primary signal for warm-season grasses to enter dormancy is a sustained drop in temperature. Growth slows dramatically when air temperatures consistently fall below 50°F. The metabolic shutdown is specifically triggered when soil temperatures remain below 50°F to 55°F for several consecutive days.
As the ground cools, the grass stops producing chlorophyll, causing the blades to lose their green pigment and turn a straw-like tan or brown. Shorter daylight hours in late fall also contribute by reducing the energy available for photosynthesis. While severe drought or extreme summer heat can trigger temporary, defensive dormancy, the predictable seasonal browning is primarily a response to cold temperatures.
Regional Timing for Warm-Season Grasses
The vast size of Texas means the onset of dormancy varies significantly from north to south, following the pattern of sustained cold fronts. Dormancy begins earliest in the northern sections of the state, including the Panhandle and North Texas, where cooler temperatures arrive sooner. Lawns in these regions typically turn brown starting in mid-to-late October and remain dormant for the longest period, often until early March.
Central Texas, encompassing the Hill Country and the Austin/San Antonio corridor, usually experiences intermediate timing. The first widespread browning is generally observed in early to mid-November, with the turf remaining dormant through late February. The later arrival of cold weather results in a shorter winter rest period compared to areas further north.
Along the Gulf Coast and in deep South Texas, dormancy is delayed and often the shortest in duration. Grasses in these warmer climates may not fully enter a dormant state until late November or early December. Consequently, they are often the first to emerge, with green-up beginning as early as mid-February following warmer weather.
Distinguishing Dormancy from Other Lawn Stress
A uniform, straw-colored lawn in winter is a sign of healthy dormancy, but not all brown grass is simply resting. Dormant grass blades will be tan, but the underlying crown—the base of the plant—remains alive and intact. A simple “tug test” can help determine the status: healthy dormant grass resists being pulled from the soil, indicating a robust, living root system.
In contrast, dead or diseased grass often displays an irregular pattern of browning rather than a uniform color change. Fungal diseases common in Texas, such as brown patch, frequently appear as distinct, circular patches amidst otherwise dormant turf. If the grass pulls out easily with little resistance, it suggests the roots have failed and the turf is dead, rather than merely dormant.
Essential Lawn Care During Winter Dormancy
Even while dormant, grass roots require minimal moisture to survive the winter. During periods without rainfall, provide about one inch of water every two to four weeks. This infrequent irrigation should be done during the morning and avoided immediately before a hard freeze to prevent turf damage.
Mowing can be stopped entirely once the turf enters full dormancy, as growth has ceased. Stop applying high-nitrogen fertilizers during this time, as they stimulate vulnerable new growth susceptible to cold damage. A late-fall application of a potassium-rich fertilizer can help strengthen the root system and enhance cold tolerance.
Winter weeds, such as henbit and chickweed, often germinate while the warm-season turf is dormant and not competing for resources. Applying a pre-emergent herbicide in the fall, before the ground freezes, creates a chemical barrier to control these invasive cool-season plants. Spot-treating any visible weeds with a selective herbicide is also effective until the spring green-up.