Preparing yards for winter will help maintain great stands of healthy turf during warmer weather.
N. Gambrell, 2019 Clemson University
It’s August, and we’ve been dealing with high temperatures and droughts, so obviously the last thing that homeowners are thinking about is preparing lawns for colder weather. Yes, colder weather is somewhere out there in the seemingly distant future, and preparations for your grasses should begin now.
Warm season grasses like bermudagrass, zoysiagrass, centipedegrass, and St. Augustine grass go into a dormant state during cooler weather, and is characterized by the loss of green color in leaves. However, your plants are not ‘dead’ and are still susceptible to environmental effects, so homeowners must create an environment that encourages healthy, yet dormant plants.
As nice as it is to keep feeding your plants nitrogen in hopes to maintain lush, green growth, it’s best to not fertilize with any nitrogen after September 1. Nitrogen fertilization after this time could cause extra vegetative growth that has a greater chance to suffer from cold damage. Instead, use a soil sample to guide you in determining whether you should apply potassium to “winterize” the yard. If the lawn does need potassium, then in September, apply muriate of potash (0-0-60), potassium sulfate (0-0-50), or Sul-Po-Mag (0-0-22). For more information on soil sampling, see HGIC 1652, Soil Testing.
It’s also a good idea to raise your mowing height by ½ inch in the middle of September if you do not plan on overseeding; for more information on overseeding bermudagrass lawns, please see HGIC 1206, Overseeding with Ryegrass. This serves to shade out winter weeds and may also encourage some deeper rooting. Irrigation is still going to be needed at times after grasses have gone dormant to prevent drying out due to warm, windy weather.
If you plan to apply a preemergent herbicide, look to apply it in mid- to late September. Night time temperatures should be in mid-50s to low-60s around the time you apply. This is also the time to be proactive in disease control. Many diseases that show up in spring actually infect grasses during this time due to the relatively warm days and expected increase in rainfall that comes with tropical weather. Local Extension Offices can provide more accurate recommendations for fungicides to limit disease development.
