There's a new weed in my town...and it's got everybody griping. It might be in your town too.
Chamberbitter (Phyllanthus urinaria), also known as Gripeweed" or "Mimosa Weed" because of it's resemblance to the mimosa tree, gives even the most seasoned lawn and landscape care professionals a major headache trying to control it. I hear almost as much griping about this weed as I do with crabgrass, and gripeweed is a much easier name to remember, so that's what I'm going to call it.
Gripeweed is an annual weed that appears in late spring or early summer and, if not controlled, will hang around until temperatures begin to cool in fall. Round fruit attached to the undersides of its leaf stems turn to seed that scatters and takes root all over the place.
Most successful strategies for keeping gripeweed at bay involve the application of herbicides. The sooner you get control the better. So, if and when you see the first few plants pop up in late spring or early summer spray them immediately!
IN LANDSCAPE BEDS
In landscape beds and other non-lawn areas you can spray and kill gripeweed with products containing glyphosate, such as Hi-Yield Killzall Superconcentrate. If you want to spend about twice the money for the same identical glyphosate product you can use Roundup superconcentrate. But why spend the extra bucks for a brand name? Whichever brand you choose, make sure it is 41% glyphosate and mix at 2 ounces to a gallon of water.
IN LAWNS
It's best to start control of gripeweed with the application of a pre-emergent herbicide (weed preventer) in early April. If you're on a D-I-Y lawn care program that uses a fertilizer/weed preventer combo product in April or early May this should help to keep this weed under control. Otherwise, you can apply just a weed preventer, such as Lebanon Team 2G or Hi-Yield Crabrass Control.
Once the gripeweed seeds have sprouted in your lawn it will be necessary to use a post-emergent herbicide (weed killer) labeled for use on lawns. However, be cautious. Some herbicides are not safe to use on all types of lawn grasses and the wrong application could have unwanted consequences. No chemical knocks this weed out quick or totally all at once, however, repeated applications of an herbicide that contains 2,4-D, such as Monterey Weed Whacker or Fertilome Weed Out with Q, are successful on bermuda and zoysia lawns. Use a product containing Atrazine on centipede or St. Augustine lawns.
OTHER TIPS
Keep in mind that the earlier you take measures to control this weed, while the weeds are young, the better success you'll have in controlling gripeweed...and the less you'll have to gripe about. On the other hand, if you like to gripe, don't to anything to control this weed and you'll have something to gripe about all summer long!
You might choose to pull the gripeweeds by hand, but if you do so, do not shake the soil from the roots, since shaking the plant can spread the seeds!
