Answers to fall and winter lawn care questions

If your lawn has had a history of winter annual weeds such as henbit, wild geranium, annual bluegrass, chickweed and lawn burweed, you can apply a preemergence herbicide during October when nighttime temperatures drop to 55° to 60°F for several consecutive nights.

What should I do about winter annual weeds in my lawn?

If your lawn has had a history of winter annual weeds such as henbit, wild geranium, annual bluegrass, chickweed and lawn burweed, you can apply a preemergence herbicide during October when nighttime temperatures drop to 55° to 60°F for several consecutive nights. This will be just before the winter annual weeds emerge. A second application may be required six to nine weeks after the initial application to achieve season-long control. Timing is very important when using a preemergence herbicide. The herbicide is applied just prior to the annual weed seeds emerging. After the seedlings are visible, it’s too late to apply the herbicide. Overuse of some preemergence herbicides can result in the lawn roots becoming stunted and weak. Follow label directions and precautions when using any pesticide, including herbicides.

Should I overseed my lawn with annual ryegrass?

 Overseeding a lawn with ryegrass to create a green lawn during the winter is mostly done for cosmetic reasons. Personally, I don’t overseed because I’m ready to take a break from routine lawn care. I take a break, my mower takes a break and my lawn takes a break.  The optimal time to broadcast the ryegrass seed is mid-October through mid-November if you wish to have a winter lawn.

What lawn pests should I watch for during fall and winter?

 Fall webworms and armyworms may continue to be active during fall until the lawn is dormant. Your lawn will look like it has been mowed very close when these caterpillars are active. Closer examination of leaf blades will reveal notched leaf edges where caterpillars have chewed.

Large patch, caused by the fungus Rhizoctonia solani, is common during the cooler weather of fall, winter and spring. In most cases, this lawn disease results in circular brown areas in the lawn. These circular areas slowly expand, sometimes becoming several feet or larger in diameter. Grass in the center of the circular patches may be green, giving a donut pattern.

Adult mole crickets may be active during fall. Watch for tunneling and areas that feel somewhat spongy as you walk in the lawn.

Fire ants can continue to be active during the fall particularly if it is moist.

For specific recommendations on controlling lawn pests or maintaining a Florida lawn, contact your UF/IFAS County Extension Office or visit this UF/IFAS Extension website http://hort.ufl.edu/yourfloridalawn.

Larry Williams is the Extension horticulture agent with the Okaloosa County Cooperative Extension Service, University of Florida. Contact Larry at 689-5850 or email lwilliams@myokaloosa.com.