Bermuda grass is a warm-season turfgrass valued for its dense growth and tolerance to heat and drought. Maximizing its potential requires a precise understanding of when and how to apply water, as timing is critical. The grass only responds favorably to irrigation when actively growing, making the transition from winter dormancy and the initial establishment phases important.
Waking Up the Lawn: Timing the First Spring Watering
Bermuda grass remains dormant during the cold months, so watering during this phase is unnecessary and potentially harmful. The trigger for initiating irrigation is tied to soil temperature, which signals the plant’s emergence from dormancy.
Begin the first deep watering when the soil temperature consistently reaches 65°F at a four-inch depth, typically correlating with nighttime air temperatures remaining above 60°F for several days. Starting too early, when soil temperatures are still cool, can encourage cool-season weeds or promote fungal diseases. Once the grass shows signs of green-up, a single, thorough watering is often enough until hotter summer temperatures necessitate a routine schedule.
Establishing New Grass: Watering Seed and Sod
Establishing a new Bermuda lawn from seed or sod requires a high-frequency watering approach compared to maintaining an established one. During the establishment phase, the goal is to keep the upper soil layer constantly moist so that delicate new roots or seeds do not dry out.
Watering Seed
If planting from seed, the top inch of soil must be kept continuously damp until germination, which typically requires watering three to four times daily for short durations. Each watering should be gentle and brief, applying about 1/8 to 1/4 inch of water to prevent the seeds from washing away. Once the seedlings are visible and reach about an inch in height, gradually reduce the frequency and increase the duration of watering to encourage deeper root development.
Watering Sod
When installing sod, the initial step is thoroughly soaking the sod and the underlying soil to a depth of at least three to four inches immediately after it is laid. For the first one to two weeks, the sod must be watered frequently, often two to four times a day, to keep the root zone moist. To check for successful rooting, gently lift a corner of the sod. When it becomes difficult to peel back and you see new white roots extending into the soil, you can transition away from the high-frequency schedule.
Routine Summer Watering: Frequency and Depth
Once the Bermuda lawn is fully established and actively growing during the peak summer season, the watering strategy must transition to deep and infrequent applications. This forces the roots to grow deeper into the soil profile, increasing the grass’s drought tolerance and resilience. The target for each watering session is to moisten the soil to a depth of six to eight inches.
A healthy Bermuda lawn requires approximately 1 to 1.5 inches of water per week, delivered through only one to three watering sessions. Watering two to three times a week allows the soil to slightly dry out between applications, which is beneficial for root health. The most effective time to water is early morning (2:00 AM to 8:00 AM) to minimize water loss and reduce the risk of fungal disease.
Local Variables: Adjusting Watering Start Times
General guidelines provide a starting point, but local conditions, such as soil type and microclimates, require adjustments to the watering schedule. Clay-heavy soils retain moisture longer and require less frequent watering, while sandy soils drain quickly and may need more frequent, shorter applications. Lawns with significant shade coverage lose less water to evaporation, necessitating a reduction in watering frequency compared to sunny areas.
Visual cues from the grass itself signal when watering must be increased. Look for signs of wilting, such as the grass blades turning a bluish-gray color or failing to spring back immediately after being walked on. Monitoring these signs of stress ensures that irrigation is applied based on the plant’s actual need, not just a fixed calendar date.