This time of year a lot of calls come in about how to manage winter weeds, especially in the lawn. Weeds like henbit, dead nettle, hairy bittercress, chickweed, and Persian speedwell are called winter annuals because they germinate in the fall and grow in the warm patches of winter and into spring where they will then produce seed (to repeat the cycle in the fall) and die once warmer, summer weather approaches. Winter perennials like wild onion and wild garlic are called winter perennials. These weeds emerge in late fall from underground bulbs and grow through those same warm periods throughout winter and spring. These weeds, however, will not produce seed like the winter annual weeds, but they will form aerial bulblets (smaller bulbs from their main bulb) and die back in the summer.

Figure 1: hairy bittercress	Figure 2: henbit leaf and flower
Figure 3: dead nettle	Figure 4: Persian speedwell
Figure 5: wild onion

Managing the Annuals

These winter annuals are already out there in your lawns and flowerbeds. Personally, I have already seen, hairy bittercress, henbit, Persian speedwell, deadnettle, and chickweed in my yard and other places. The henbit is already large in some areas, where I’ve seen tiny patches of hairy bittercress; sizing will just depend on the growing conditions of the particular area.

SO… as soon as you see them, spray them with an herbicide listed for that area (preferably before they develop seeds)! Look for herbicides containing dicamba, MCPP, and 2,4-D, but ALWAYS check the label so that you know that that particular herbicide controls the weed in question, application methods and timing, and that it will work with the lawn species or area in which you want to apply it. The last thing you need is to spray your yard for a few weeds and then end up killing your whole yard because it wasn’t suited for your lawn type!

Managing the Perennials

If there are only a few of these weeds, one of the best things you can do is to just dig them up by hand. It might take an hour or two, but it will save you some time and money later on by reducing your mowing and herbicide applications. However, if you have way too many to count or do not wish to dig them up one-by-one, herbicide options are available. For wild onion and wild garlic, there are not a lot of preemergent options available so that means they will have to be treated when they emerge (instead of before they emerge).

Recommended herbicides include those containing Imazaquin, 2,4-D, dicamba, nd MCPP. More than one TIMELY application may be necessary, because they are perennials and can be more resilient.

Again, ALWAYS be sure to READ THE LABEL for application methods and timing, and that it will work with the lawn species or area in which you want to apply it.

Interesting ID fact – wild onion and wild garlic are very similar, but to tell them apart (without flowers or digging up their bulbs), you can cut their leaves and see that wild garlic stems are hollow while wild onion stems are not.

 Other Things to Note

• If you do not know what weeds you have or need help figuring out if a certain herbicide will work for your area in question, PLEASE give me a call; Cari Mitchell, 828-632-4451 or email me at cari_mitchell@ncsu.edu with a picture of the weed and/or pesticide in question.
• You will want to wait until temperatures get to at least 55 degrees F so that the herbicide can work properly.
• Bees and other pollinators LOVE winter flowering weeds because this is one of their first food sources since early fall. If you have waited too long to control these weeds, consider letting them go this time for the pollinators. If you do want them gone and they are in flower, I recommend mowing them or trimming them with a weed eater so that most of the flowers get knocked off. Wait a day or two after this and then spray the appropriate herbicide. This will prevent pollinators from visiting flowers that have been contaminated with poisonous herbicides.
  

  Figure 6: bees on chickweed