Asked April 20, 2021, 4:22 PM EDT
Frederick County Maryland
Take a look at this:
You can get herbicides containing 2,4 D which should kill speedwell but not kill your grass. Follow all label directions.
If you live in MoCo there are limits to your use of chemicals on the lawn. https://www.montgomerycountymd.gov/lawns/law/
I found three "natural" herbicides that are labelled to kill speedwell, may meet MoCo requirements and does not kill lawn areas: Fiesta, Bonide Weed Beater FE and Leonard Selective Broadleaf Herbicide. There may be others. Always read the label and follow directions.
These are new to me and I have no experience with them or how well they work. You may want to contact the Turf Center at the Un MD.
On 04/20/2021 5:55 PM Extension Foundation <firstname.lastname@example.org> wrote:
It should work in 1-2 days or less. There are several possibilities:
1. Do an internet search on "speedwell", IMAGES tab, to be sure it really is speedwell, and what type of speedwell.
2. Only one variety of speedwell is specifically listed in the instructions as one of the weeds targeted. You may have a different speedwell. If yes, confirm application rate, 2, 4 D concentration, temperature, etc.
3. It is possible the product you used was degraded due to improper storage (shelf life/age, temperature, subjected to freezing).
4. Spray again and wait another 2 days. If the speedwell is still 'happy and healthy', call the manufacturer's contact number on the product you are using and as ask them why it is not working. Maybe they will send you a newly manufactured substitute or refund your money. If they refund you, purchase another manufacturer's product containing 2,4 D and read the instruction before purchase to be sure speedwell is listed as a targeted weed (and see if there is a recent manufacturing date). If in doubt call the manufacturer and ask if speedwell will be killed and confirm how to use the product.
5. If all else fails, try using a different herbicide.