Bermuda grass is a warm-season turf that thrives in summer but enters winter dormancy as temperatures drop. This natural process conserves the plant’s energy and protects its root system. Preparing the lawn for dormancy requires changing management practices, and the timing of reducing water is important for the grass’s survival. Stopping irrigation abruptly causes undue stress, making a gradual transition fundamental for successful winterization.
Identifying the Seasonal Trigger
The decision to reduce irrigation should be based on environmental cues, not a calendar date. Bermuda grass growth slows significantly when the soil temperature drops below 65°F, and it begins to lose its vibrant green color. This temperature, measured at a four-inch depth, is the most reliable indicator that the turf is entering its fall transition phase.
When daily high air temperatures consistently fall into the 50s, the grass begins the full process of dormancy, turning a tan-brown color. This shift is a physiological response to shorter daylight hours and cooler conditions, prompting the plant to relocate carbohydrates to the rhizomes and stolons for winter storage. This transition occurs earlier in northern areas compared to the Deep South.
The first expected hard frost serves as a final marker for the end of the growing season. A frost rapidly kills the above-ground leaf tissue, accelerating the visual browning. Paying attention to these temperature drops and the lawn’s visual cues helps pinpoint the correct window to initiate the gradual reduction in watering.
The Tapering Process for Winterization
The process of reducing water is known as “hardening off,” which slows the grass’s metabolism and prepares its cells for cold. Stopping watering suddenly causes immediate drought stress and depletes energy reserves needed for winter survival. A gradual tapering schedule over two to four weeks allows the turf to naturally acclimate to drier conditions.
If your lawn has been receiving water three times a week, the first step is reducing that to once a week for seven to ten days. Following that, reduce the frequency again to once every two weeks. This controlled drought forces the grass to slow its growth and concentrate solutes within its cells, increasing cold tolerance.
During this transition, monitor for signs of overwatering, which poses a significant threat to the plant’s crown. Excessively wet soil in cold temperatures creates conditions conducive to fungal diseases like spring dead spot or crown hydration. If the crown absorbs too much moisture during a winter thaw, a subsequent rapid freeze can rupture the cells, causing winter kill.
The final step before the lawn turns completely brown involves a deep soaking application of water. This single, thorough watering should saturate the root zone six to eight inches deep, providing a reservoir of moisture for the roots and rhizomes during dormancy. This deep saturation must occur when temperatures are low and the grass is visibly slowing down, supporting the root system without encouraging late-season growth susceptible to frost damage.
Dormancy Maintenance Watering
Once the Bermuda grass has completely turned brown and is fully dormant, the goal shifts from encouraging growth to preserving the root structure. Although the grass is not actively growing, the roots and crown remain alive and require minimal moisture to survive the winter. Ignoring the lawn entirely can lead to desiccation, the death of the plant from drying out, particularly in areas exposed to high winds or prolonged dry spells.
To prevent desiccation, a light maintenance watering is necessary if the area receives no natural precipitation for an extended period. The guideline is to apply about one inch of water every four to six weeks during a drought, but only when temperatures are above freezing. This light soaking is sufficient to keep the root mass from completely dehydrating without saturating the soil.
It is crucial to apply this maintenance water only when necessary and during a period of thaw to avoid the risk of crown hydration. The plant’s water needs are significantly lower, so this occasional, light irrigation is strictly a survival measure. By providing this minimal moisture, you ensure that the underground structures have the reserves to remain viable, enabling a strong and rapid green-up when the soil temperatures finally climb back above 65°F in the spring.