With cooler weather arriving, some golf facilities will face the decision of whether or not to overseed ultradwarf bermudagrass greens. The decision becomes more complicated if the greens are in suboptimal condition. Course managers must decide if they should overseed to produce acceptable winter playability and try to cover up thin, mottled bermudagrass, or if it is better to skip overseeding and focus resources on recovery and long-term turf health. This article outlines key factors to consider when navigating this critical decision.
Understand the Starting Point
First, you need to accurately assess the current conditions of your bermudagrass greens. If turf cover is significantly reduced, overseeding will likely further compromise the bermudagrass base. However, this is a risk that may be worth accepting if overseeding is the only way to provide decent winter playing conditions. On the other hand, if the greens are mostly intact with only moderate thinning, overseeding may be a viable option to maintain winter playability without jeopardizing long-term performance. Bermudagrass with a strong root system and healthy organic matter levels in the rootzone is generally more tolerant of the competitive stress introduced by overseeding.
Evaluate Winter Play Expectations and the Consequences of Overseeding
A critical factor in this decision is golfer expectations for putting green quality during the winter months. Courses in areas with heavy winter play often feel pressure to overseed, regardless of turf conditions. In such cases, it is important to communicate clearly with leadership about the trade-offs. While overseeding may deliver acceptable winter surfaces, it may also delay bermudagrass recovery in spring, especially if the turf is already compromised.
Course managers must also consider the risks of overseeding. There is never a guarantee that overseeding will fix the issues that come with thin bermudagrass cover. The seedlings that emerge often reflect the existing surface irregularities. Once you start mowing at a lower height of cut it may damage or displace the young seedlings. If you are able to establish a robust overseed stand, the competition for water, nutrients and sunlight will compromise the ability of the understory bermudagrass to recover in the spring. Courses that overseed when bermudagrass is weak will need to plan on thinner bermudagrass cover during the transition phase. Many courses in this situation will have to close all or part of the greens in spring to plant sprigs or lay sod. Overseeding is not a “set it and forget it” process and does not offer instant gratification. It requires sustained inputs of water, nutrients and labor to establish and manage cool-season turf, especially during variable fall and winter weather.
Alternative Options
Instead of overseeding, you may consider using pigment applications, light and frequent topdressing to help smooth any irregularities and increase surface temperatures, nitrogen inputs, and even using turf covers overnight to expedite bermudagrass growth and recovery in the fall. While the surfaces may not be perfect, the absence of overseed competition will facilitate much faster and better bermudagrass recovery in the spring and will help the bermudagrass develop a stronger rhizome base.
Final Thoughts
There is no one-size-fits-all answer when it comes to overseeding bermudagrass greens that are not in good condition. The best approach balances immediate playability needs with long-term turf health and sustainability. Accurate assessment, clear communication with stakeholders and strategic planning are key to making the right choice for your course.
West Region Agronomists:
Brian Whitlark, regional director, West Region – bwhitlark@usga.org
Ross Niewola, agronomist – rniewola@usga.org