Q: Most of my Zeon zoysia backyard is still dead looking. My lawn service applied preemergent and fertilizer earlier this year. In the last four to five weeks, it is starting to slowly turn green. However, the green grass isn’t getting taller. If high nitrogen fertilizer was applied in January, February and March, could that have kept my yard from greening up? JS, Sandy Springs
A: Sometimes figuring out what’s wrong with a lawn involves observing the pattern of damage you see. You sent several photos of a brown lawn. In your case, the pattern does not look like a leaf disease that would be common in spring. Instead, it looks like environmental damage that happened last year or earlier this spring. Environmental damage might include fertilizing too late last year or too early this year or mowing too low. Those three things would have made the grass tender so that it would be killed by winter cold. Applying a high nitrogen fertilizer in early spring can severely harm dormant grass. When the grass wakes up on a warm day, it tries to grow in response to the fertilizer. But freezing temperatures quickly kill the revived grass crowns. You should closely examine your lawn to see if there are any green sprouts that could be nurtured to bring the lawn back to health. But if you have a dead lawn, you have a dead lawn, and you’ll have to put in new sod for it to be green again.
Q: I have Bermuda grass coming up in my zoysia lawn. Is there a way to eradicate it chemically? Pete Dawkins, email
A: The selective removing of one perennial grass from another perennial grass is a tedious project requiring a lot of diligence. It is very hard for weed control chemicals to tell grasses apart. Bermuda grass and zoysia grass are similar in growth habit and appearance. So it is very hard to get Bermuda grass out of a zoysia lawn.
The post-emergence herbicide Fusilade II (active ingredient fluazifop-P-butyl) is labeled by one manufacturer for control of Bermuda grass in zoysia. However, the label states: For use only by commercial or licensed applicators when applications are to be made in or around homes. Not for use on home lawns.
Consider using Acclaim Extra (active ingredient fenoxaprop-p-ethyl). It is labeled for Bermuda grass suppression in a zoysia lawn. Unfortunately, there is no herbicide that will completely kill Bermuda grass in a zoysia lawn. However, you can use Acclaim multiple times to suppress the Bermuda enough to allow the zoysia to fill in and smother it out eventually.
Email Walter at firstname.lastname@example.org. Listen to his occasional garden comments on “Green and Growing with Ashley Frasca” Saturday mornings on 95.5 WSB. Visit his website, www.walterreeves.com, or join his Facebook page at bit.ly/georgiagardener for his latest tips.