Given the warm weather we had last week and the mild temperatures in the latter part of this week, I have had numerous calls regarding lawns! In Eastern NC we have warm-season grasses, almost exclusively, here in Eastern North Carolina. The main warm-season grasses we grow are Bermuda, Zoysia, Centipede, and St. Augustine. This means that much like a bear, our lawns go dormant during the cool season only to come back when soil temperatures begin to climb into the 60s. Also like a bear, when they begin to grow in the spring they can be a little slow to wake up (this is called green-up) but when temperatures start climbing, they begin to really take off. However, it is a little early right now to worry much about green-up.

Taken at the Beaufort County Extension Center – The weed in the picture is Henbit. This is the weed that you see in the farm fields this time of year that causes them to have a purple hue. This is a winter annual weed that can be prevented with a pre-emergent application of herbicide that is safe for your turf, applied in mid-September through mid-October.

It is not too early to worry about weeds, however. One thing that we can be working on, is getting a pre-emergent product out to keep annual weeds from germinating. There are several products that contain a single chemical or a combination of chemicals, that prevent the germination of weeds like crabgrass. This aids our lawns by keeping the competition for resources to a minimum. Pre-emergent products can be very species, or even cultivar-specific. This means it is important that you know what type of grass that you have and you do your homework before selecting a product. For instance, centipede and St. Augustine are very sensitive to products that contain 2, 4-D but Bermuda is not.

Timing is another very important factor in preventing annual weeds in your turf. When trying to work on spring/summer annuals, it is best to get your application in place by late January – early February. These applications will have roughly three to four months of activity, which will get us into the late spring/early summer. It may be necessary to apply a second application of pre-emergent in early June when we are experiencing a good crabgrass year.

In warm season grasses, especially centipedegrass, it is a good idea to stay away from weed and feed products. The timing of the application and the growth habit of centipede, do not make a good combination with weed and feed type products. The feed portion of these products is the fertilizer that tells our grass to wake up and grow. The growth habit of centipede is to grow long stolons across the soil surface. These stolons then root at every node and grow new plants. The weed portion of these products is typically a pre-emergent chemical (root inhibitor) that will prevent centipedegrass from being able to root when it grows.

Taken at the Beaufort County Extension Center – The weed in the picture is Wild Garlic (not wild onion). Pre-emergent herbicides will not work on this weed, use a post-emergent such as those with the active ingredients metsulfuron, 2, 4-D, or metsulfuron+rimsulfuron.

Lastly, let’s talk about the timing of the application. It is not a good idea, in most cases, to fertilize any warm season grass until full green-up. In most years, this occurs near the early part of May. Even though your yard may look green, full green-up doesn’t occur until soils reach a temperature of around 70°F for several consecutive days. Going back to the timing of the weed and feed products, we are supposed to put those out between now and early March. In effect, what we are doing is telling our grass to grow but preventing it from rooting. This sets up the perfect storm for a spring kill. The new growth is not hardened off (not able to withstand the cold). During a late-season freeze or even a frost, we risk killing our entire lawns! I think we can all attest to how crazy the weather in Eastern NC can be!

As with all chemicals, the label is the law! Make certain to store and apply chemicals according to the label for the labeled target pest. Make certain to wear proper attire and apply in a fashion consistent with the label as well.

If you are having trouble with growing in your home landscape, call the Extension office at (252)946-0111 or email Gene Fox at gene_fox@ncsu.edu. I will have a commercial ornamentals and turf class coming up in February/March. If you need pesticide or landscape contractor credits, please keep an eye out for details on this class. I am also having a series of classes beginning in February that will go into soils, fruits, vegetables, ornamentals, and lawns. You can come to all or one, whichever you like. Keep an eye on our website or the Beaufort County Master Gardener Facebook page for more details or register at What You Need to Know To Grow. Until then, Happy Gardening!