Fall is the best time to control dandelions and other perennial weeds,
such as ground ivy. In fall, the plant begins moving nutrients to the roots for storage instead of to upper
plant parts for continued growth. If herbicides are applied at this
time, the chemicals are transported to the roots along with the nutrients, killing the entire plant instead of just the parts above
the soil surface.
The best control measures to use depends largely on correctly identifying the weed
present, but one of the keys to controlling weeds effectively is making
herbicide applications at the right time of year and for many broadleaf,
perennial weeds like violets, ground ivy, and dandelions fall is an
excellent time to get them under control. Fall control of annual weeds like crabgrass, foxtail, etc. is not necessary. These weeds will die during the
winter and do not germinate from seed until spring, making fall
control unneccesary.
Many winter annual weeds, like field pennycress, shepherdspurse,
chickweed and henbit, should also be targeted for controlled in the
fall. Winter annual weeds germinate in fall, grow into a small rosette
then overwinter and resume growth in early spring. A fall broadleaf
pre-emergent application, such as Preen (trifluralin), Surflan,
Pendimethalin or Dimension, should be applied in the fall to prevent weed seed germination, just as it does in the
spring.
Before applying any herbicide, always have the weeds identified and follow the manufacturer's directions. Use caution when applying herbicides around landscape beds since accidental spraying or spray drift can damage shrubs and ornamental plants.
Additional Information
New Jersey Weed Gallery - Rutger University
Henbit Information - UC Davis
Shepard's Purse - University of Illinois
Pennycress - Virginia Tech
Ground Ivy - Virginia Tech
Borax on Ground Ivy: Boon or Bane? - Iowa State University
