Early spring weeds flowering

Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.

April showers bring May flowers. The end of April and early May is typically the time of year when many turf areas are full of bright colorful flowering weeds. Now if you don’t mind some color and are patient, your best course of action is what I refer to as the go back inside and sit down method, i.e. do nothing. However, if you’re trying to eliminate some pesky weeds from your lawn, a very good time to control many of these broadleaf bandits is at flowering. Just as a reminder, the best time to control many broadleaf weeds is during the fall – but we’ll save that one for our annual fall roundup issue.

Currently purple deadnettle, common chickweed, henbit, and shepherd's purse are all flowering in the landscape. These weeds are winter annuals and are always the first to flower in the spring. The time window to control these weeds is very small and it is generally not advised to spray anything as these weeds will complete their life cycle quickly and not be a factor in the turf until the fall when they can be effectively controlled by a properly timed herbicide application.

Dandelions are also coming on strong right now and will no doubt be extra frisky after the recent rainfall. The normal temptation is to go after the dandelions at peak flowering, but waiting until the end of the flowering cycle is a much more effective time to actually kill some plants. If you spray early, you will only burndown the top portion of the plant and it will likely be necessary to make a repeat application around Memorial Day to clean up the re-growth.

For additional information and models on predicting weed flowering throughout the region take a visit to www.gddtracker.net. This website is designed for turfgrass professionals to help predict optimum control windows for many weeds and for Poa annua seedhead suppression on golf courses.

Dr. Frank's work is funded in part by MSU's AgBioResearch.

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