​PPDL Picture of the Week

October 2, 2017

 

Fall, a Great Time to Control Perennial Broadleaf Weeds

John Orick, Purdue Master Gardener State Coordinator, Department of Horticulture and Landscape Architecture

Fall is the prime time of the year to control perennial broadleaf weeds like dandelion, buckhorn plantain, ground ivy, violet, clover, etc. (See photo). As winter approaches, food reserves in the weed plants will be moving toward stems and roots. Herbicides sprayed onto the plants during fall will move with these reserves to offer better control of perennial broadleaf weeds compared to spring herbicide applications. As with most pest control, applying the appropriate pesticide product is just one part of a comprehensive approach to controlling the pest. This is also true for weed control in lawns. Lawn care practices such as choosing an adapted grass species, fertilizing cool-season turf at least once per year in the fall, mowing at the proper height, watering properly, correcting poor drainage, core aerifying compacted areas, and treating insects and disease when feasible, are all ways to encourage healthy turf growth that competes with weeds.

Here are some tips for controlling perennial broadleaf weeds in home lawns:

  • Identify problem weeds and their life cycle. Herbicide product choice and application timing vary depending on the weed species and the plant’s life cycle. Perennial (life cycle) broadleaf weeds are best controlled in the fall.

  • Liquid products applied by spraying the herbicide directly on the plants are more effective than granular herbicide products.

  • Apply only enough spray to cover the weed leaves but not drench them.

  • Avoid spraying broadleaf herbicides during extreme air temperatures. Temperatures higher than 40 degrees F and lower than 80 degrees F are recommended.

  • Apply broadleaf herbicides on a sunny day to more effectively control problem weeds.

  • Apply broadleaf herbicides during a rain free period of at least 6 hours.

  • Avoid spraying broadleaf herbicides on windy days to reduce the risk of drift to non-target plants.

  • Do not apply herbicides to drought-stressed turf.

  • Read the herbicide product label for restrictions on re-seeding after applications.

For more information on weed control and other lawn care practices, visit www.turf.purdue.edu.

Resources:

Control of Broadleaf Weeds in Homelawns (AY-9-W), https://www.extension.purdue.edu/extmedia/AY/AY-9-W.pdf

 

Weed of the Month (Weed ID),  https://turf.purdue.edu/weedofthemonth.html

 

Lawn Improvement Programs (AY-13-W), https://www.extension.purdue.edu/extmedia/AY/AY-13-W.pdf

 

7 Simple Steps to a Better Lawn (AY-32-W) https://www.extension.purdue.edu/extmedia/AY/AY-32-W.pdf

 

 









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​Click image to enlarge


 
Perennial broadleaf weeds growing in a home lawn. (Photo by John Orick)