DALY: Answering questions about lawn weeds, spring freezes and liriope

Tim Daly

Gardening columnist Tim Daly answers the following questions from readers:

Question: My bermudagrass lawn has many weeds. What can be done to control the infestation and improve the quality of it?

— Ellen in Sugar Hill

Answer: Ellen, you should apply a pre-emergent herbicide to control spring and summer weeds that are germinating, such as crabgrass. Local garden centers sell. Most consists of granules that require an application of water after broadcasting them. Check the label for specifics.

Avoid products that are “Weed and Feed,” which consist of both the herbicide and fertilizer. Warm season grasses, such as bermudagrass and zoysiagrass, should not be fertilized until after they green up in April. The fertilizer will stimulate growth and could bring the grass out of dormancy prematurely, making it more susceptible to freezing temperatures.

For the existing weeds, you will need to apply a post-emergent herbicide, such as some of the Bayer Advanced, Ortho and Spectracide products. Please observe all label directions and safety precautions when using pesticides.

Q: I see several plants, such as tomatoes and peppers, for sale in local garden centers. To my understanding, they are not tolerant of freezing temperatures. Are we past the danger of frost or is the possibility of below-freezing temperatures still a concern?

— George in Grayson

A: George, do not plant anything that is not tolerant to below-freezing temperatures. Although we experience warm weather this time of the year and frost-tender plants are for sale at local stores, the risk of late-season freezes is a real possibility. When they occur, the Extension office receives calls from residents who had put out these plants, and our response to them usually is to remove the plants and replace. The average last day of frosts in our area is April 15, so plant these sensitive plants after that day.

Q: I have a significant amount of liriope in my home landscape. It has a rough, unsightly appearance. Could I cut it back to the ground? Is now a good time? Can I use a lawnmower?

— Martha in Norcross

A: Martha, liriope is commonly used as a groundcover in the landscape. It thrives in both sun and shade and is an excellent replacement for turfgrasses in shady sites. You should cut it back to the ground right now before it generates new growth. For small areas, hand snips can be used. Lawnmowers are suitable for larger areas of liriope. Cut it to 1 inch in height with a sharp blade. Before mowing, carefully walk through the area to see if any rocks, sharp objects or anything that could damage the mower are present and remove them. After cutting, in a few weeks, you will see new growth emerging. Use a complete granular fertilizer, such as 10-10-10, and broadcast evenly over the liriope.

Timothy Daly is an Agricultural and Natural Resource Extension Agent with UGA Extension Gwinnett. He can be contacted at 678-377-4011or tdaly@uga.edu.