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.
Seedheads are starting to appear in big numbers in lawns this week. (see photo) This is a normal occurrence that happens every May across Michigan. Most of the common turfgrasses found in lawns produce seedheads including Kentucky bluegrass, perennial ryegrass and of course Poa annua (otherwise known as annual bluegrass). Seedheads not only detract from the appearance of the turf but the seed stalks are tough to mow so make sure you have a sharp mower blade. However, even with a sharp blade you still may see a sheen or whitish look to the turf after mowing due to the seed stalks. Resist the urge to try and mow down the seedheads by lowering the mowing height. Any golfers out there will tell you that Poa annua can produce seedheads at putting green mowing height so lowering the mowing height on the lawn is not a recommended approach.
Some things to watch for over the next couple of weeks as the seedheads hit peak. The turf may start to look stemy and lose density. This is natural. It will come back strong once this period of seedhead production ends. Basically right now the plant is putting a lot of energy into popping those seedheads. Once it’s done, the turf growth and density should return to normal levels.