Preparing Warm Season Turfgrass for Winter
It’s October, and in the northern hemisphere we’re heading into winter. For many in the temperate areas this means anything from leaf fall, wet and soft playing conditions to frost and snow. In our last article we covered the specific challenges facing courses in the northern hemisphere, if you missed it, check out the full article on How to Put Your Greens to Bed.
In this article however, we’re concentrating on the warmer climates. In particular the sun-soaked regions of the South and Southeast USA where warm season turfgrasses prevail.
Species such as:
- Bermudagrass, popular choice with its fine leaves and resilience to drought.
- Seashore paspalum is another golf course favorite, suitable for frequently mown areas. It’s improved in quality due to recent breeding programs and requires less fertilizer than Bermudagrass. This grass is also tolerant of saltwater and can maintain good quality in shaded conditions.
- Zoysia grass is often preferred for fairways and roughs because it requires less maintenance and fairs well in low nitrogen conditions.
- Kikuyu grass is another viable option for fairways and roughs with low nitrogen needs but requires regular watering during droughts. It’s prone to diseases like brown patch disease and requires routine verticutting due to excessive shoot growth.
Preparing these warm-season grasses for winter golf requires specific maintenance practices in order to successfully endure the colder months and the high turnover of golf rounds played.
Mowing Height Adjustment
With winter’s approach the height of cut should be lowered to the standard required for the course in your region. The lower mowing height during fall, apart from providing the required playing conditions, allows for better sunlight penetration and air circulation, reducing the risk of disease. Going too low can be detrimental as an adequate leaf surface is needed for photosynthesis and food storage during winter.
Aeration and Dethatching
The optimal window for aerating warm-season grasses is typically mid to late spring. If you’ve missed this springtime opportunity then early fall provides a second chance to aerate. Aerification allows for more efficient delivery of air, water, and nutrients directly to the roots. Combined with aeration, dethatching, the removal of accumulated layers of dead grass and organic matter from the upper surface, can significantly enhance the overall health of your turfgrass. Organic matter buildup can be more problematic during winter due to the slower decomposition rates. Ensuring there is no excessive thatch will prevent it from providing a source of pests and diseases.
These practices serve to alleviate soil compaction, promote root growth, improve nutrient absorption, and reduce disease pressures. These are also particularly crucial in the warmer southern regions where warm season grasses are dominant.
Nutrition
The fall season presents an excellent opportunity to fertilize warm season playing surfaces. It allows for the necessary nutrients for optimum root growth and resilience to wear and stress. A balanced nutritional program, geared to the local growth environment and guided by regular soil analyses is the key to healthy sustained growth. This is an essential maintenance practice for warm season turfgrasses. As the turfgrass prepares for the winter ahead, fall fertilization is key to ensuring the turfgrass surfaces retain color and vitality through the busy winter season and allows for a successful beginning to the upcoming spring.
Irrigation
Another important maintenance requirement is to continue watering the turfgrasses appropriately. Although warm season turfgrasses can go dormant through winter, they still require some moisture to stay alive. Despite the reduction in temperatures experienced through winter, it is important to maintain a regular irrigation schedule (obviously not to the same scale as during summer). Despite entering dormancy, warm-season grass still requires hydration. Keeping the roots well-hydrated without overwatering is essential. Irrigation, possibly once a week should suffice during winter. Consideration must be given to local conditions with possible adjustments if there are rainfalls. Ensuring the warm season turfgrass has consistent hydration is essential to protect it against shallow root formation, stress, and disease susceptibility.
Weed and Pest Control
Weed control is another important aspect of winter maintenance for warm season turfgrasses. Weeds compete with the turfgrass for nutrients and water and are unsightly and can impede play. Fall serves as an ideal time to control any existing weed problems. Weeds, being less aggressive during this season, are more susceptible to control measures. Using pre-emergent herbicides can restrain weed seed germination, while post-emergent herbicides can effectively eliminate any present weeds. Addressing weed issues before the onset of colder weather can prevent further damage during winter when the grass is less resilient.
Providing Winter Color
Golfers expect golf courses to be green, even during dormancy in winter. Two things that can help with this are overseeding, and/or the use of colorants or pigments.
For some regions fall is the time to consider overseeding with cool-season grasses. The practice of seeding cool-season grass varieties, such as ryegrass, over existing warm-season turfgrass ensures a lush green color in winter. If carefully managed, the overseeding process can avoid competition between the two grass types, ensuring a seamless transition as spring returns.
The second option is to use turfgrass colorants or pigments, these are proprietary products specifically designed to provide an appealing natural green color to the turfgrass surfaces.
Fall Renovation and Repair
The season of fall also marks an appropriate time for renovation and repair prior to the bust golf period. If your turfgrass has thin areas or patches, fall is the ideal time for reseeding or sodding, resulting in a uniform and healthy playing surface come spring.