The Growing Season
Does your warm-season, hybrid Bermuda grass look sparse or weak? The culprit may be continuous overseeding. Often times, this is due to the competition for nutrients between the Bermuda grass and the perennial Ryegrass used in fall overseeding. Overseeding leaves the Bermuda needing recovery time to build strength and vitality before the next growing season.
Overseeding in the fall does not allow Bermuda grass to complete its normal growing cycle before winter dormancy approaches. Much like a bear preparing for hibernation, Bermuda spends the weeks and months prior to the cold season storing the reserves it needs to keep its roots and stems alive through the winter. Overseeding interrupts this process and often, die-back results in the root system. The effects of interrupting this process are seen in the spring when weather conditions are right for Bermuda to begin growing again. The thick, tall Ryegrass will keep the Bermuda shaded and cool, which prolongs the dormancy period. By keeping the Bermuda dormant longer, the percentage of Bermuda that runs out of food before it can begin to photosynthesize increases.
When the Bermuda does come out of dormancy, it must contend with the Ryegrass for nutrients while the Ryegrass is at its strongest. Ryegrass is a fierce competitor for all the resources required for Bermuda to grow: sunlight, water, nutrients and even oxygen. During early spring, the Bermuda is at a disadvantage during the time it should be strengthening to withstand the extreme heat and dryness of a typical Arizona summer. By mid-summer, the Ryegrass dies out and physically impedes the Bermuda’s ability to spread. The dead Ryegrass must be removed through dethatching, which may further injure and set back the Bermuda. In most cases, the Bermuda does not get the time needed to recover because overseeding starts again in just a few weeks.
We recommend suspending the overseeding process for at least one season to help restore the root system and nutrients of the Bermuda grass.
During the Dormant Months
Not overseeding turf areas with winter Ryegrass changes the focus of your seasonal practices. The steps below will help you prepare for the next season of Bermuda grass during the winter:
• Mow twice monthly to maintain a clean appearance and
• Control weeds
• Top dress to fill in holes and areas of compaction
What to Expect
Bermuda grass can stay green until the first frost, usually the middle of December. Around the middle to end of March, when nighttime temperatures begin to approach 60 degrees, Bermuda starts to grow again and returns to a regular mow and care cycle. It should also be noted that by not overseeding there are significant savings that can be helpful to any household. Click the link for an article written by a Water Conservation Specialist, highlighting some of the additional benefits.