Winterizing Lawns

Preparing your lawn for colder weather may be the last thing on your mind right now. But, now is the time to start preparing your lawn for those colder temperatures.
Warm season grasses like centipedegrass, bermudagrass, zoysiagrass, and St. Augustine grass go into a dormant state during cooler weather. Dormant grass is characterized by the loss of green in the leaves. This does not mean your grass is dead. Your grass is still susceptible to environmental effects during the dormant season, so homeowners must create an environment that encourages healthy, dormant plants.
Feeding your plants nitrogen does promote lush, green growth. However, it is not best to fertilize with any nitrogen after September 1st. Nitrogen fertilization after this time can cause extra vegetative growth that has a greater chance to suffer cold damage. Use a soil sample to guide you in determining whether you should apply potassium to “winterize” the yard. If the lawn does need potassium, follow the recommendations based off the soils report. These recommendations would be to apply potash (0-0-60), potassium sulfate (0-0-50), or Sul-Po-Mag (0-0-22).
Raising your mowing height by 1/2 inch by the middle of September is a good idea. This shades out winter weeds and encourages deeper rooting. Irrigation may still be needed at times after grasses have gone dormant to prevent drying out due to warm, windy weather.
Preemergent herbicides should be applied by September 15th – October 1st. The night time temperatures should be in the mid-50s to low-60s around the time you apply. Look for preemergent herbicides with the active ingredients prodamine, isozaben, dithiopyr, pendimethalin, benefin + trifluralin, oryzalin, or benefin are safe to use on bermudagrass, centipedegrass, St. Augustinegrass, and zoysiagrass. As always, follow the label when using herbicide. The label will tell you the rate at which you need to apply and if the product needs to be watered in. Preemergent herbicides are generally effective for 6 to 12 weeks depending on the product. For season-long control, make a second application nine weeks after the first application.
For more information on winterizing lawns, please visit the Home and Garden Information Center website at hgic.clemson.edu. Tune in on Tuesday nights to watch “Making it Grow” at 7 p.m. on SCETV or mig.org. Email Outen at [email protected]
*
Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, gender, religion, national origin, disability, political beliefs, sexual orientation, gender identity, marital or family status and is an equal opportunity employer.