Question

Is anything effective on dollar weed?

Asked by wendy allen
Fairhope, AL

I have large areas with dollar weed taking over. The roots are so deep.

Answer

Richard Heller

Answered by Richard Heller

New Rochelle, NY

Greener by Design

August 19, 2010

Dollar weed is a rhizomous perennial, which makes it difficult to remove by hand.

  • Plants with rhizomes spread by sending out runners, and so though they can be reduced by hand-weeding, this inevitably leaves pieces of rhizomes in the soil, so they'll most likely re-sprout.
  • Clemson University recommends that gardeners consider controlling dollar weed rather than eradicating it.
  • They state that like many lawn weeds, dollar weed thrives in poorly drained soils that have constant moisture and that the most surefire way to reduce and control weeds like dollar spot is to change water habits and increase grass heights.

You can help your lawn better compete against the dollar weed: grass prefers deep watering at longer intervals, twice a week. If temperatures are excessively high and there has been a long drought, three times a week may be necessary.

  • Water for longer periods with longer intervals between watering encourages root development in grass and starves weeds of water.
  • Allowing the grass to grow to three inches reduces the light that reaches shorter weeds like dollar weed. 
  • Additionally, I would recommend amending your soil so that it drains better, and testing the soil's pH levels. pH levels are the number-one cause of weak lawns, and weak lawns are more prone to weeds and insect infestations.

Dollar weed is edible and can be used in salads if NOT grown in a chemically treated lawn where pesticide residues may still be present, claims the Jacksonville Seed Exchange.

Some bloggers contend that dollar weed can be killed with baking soda applied to wet leaves. There is also an organic product called Avenger that claims to work on broadleaf weeds such as dollar weed. This product is citrus-based.


For more information:

Read Richard Heller's Q&A "My parents want to add a bit of lawn to their yard for a bocce ball area. Is synthetic lawn a good idea?"

Also read Sherri Osaka's tips "Take Steps toward a Poison-Free, Natural Lawn".

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