Experts agree that September is a great time to get the weeds growing in your lawn under control. At the risk of sounding like a politician, early fall weed control is the “proactive” approach to weed control.
Most of us take the “reactive” approach of killing dandelions and other lawn weeds in the spring when we see them flowering. After we wipe that initial round of flowering weeds out, we’ll have a lovely lawn all summer. Unfortunately the seeds of dandelions from other, untreated areas around our yard are blowing in and sprouting in our lawn. These little seedlings of the perennial weeds are small and go unnoticed. They’ll survive the winter and burst into flower with the first warm days the following spring.
With this in mind the “proactive” gardener will treat his or her lawn in September with a liquid spray weed killer or a “winterizer” type lawn food with granular weed killer added. Unlike regular spring “weed ‘n feed”s , the “weed ‘n winterizer” contains more phosphorus that nitrogen so it’ll enhance the natural root growth that occurs in the fall.
Higher nitrogen foods should be avoided in the fall since blade growth (stimulated by nitrogen) is detrimental to a lawn that’s in “root growth mode” if you will. Apply granular “winterizer ‘n feed” when the lawn is moist so the weed killer dissolves on the leaves of the weeds where it is absorbed into the weed. The longer this dissolved weed killer remains in contact with the leaves of the weeds, the better it will work. If the weed killer is washed off the leaves before 48 hours have passed, it won’t be very effective killing the weeds. Liquid weed killers are applied the same as they are in spring (sprayed onto the leaves of the weeds in the lawn) and the same “not watering for 48 hours” rule applies with them as well.
By killing the young weed seedlings that are growing in your lawn this September, you’ll find that you won’t have to take the “reactive” measure of trying to fit weed killing into a busy spring gardening schedule. You’ll wipe out a higher percentage of the weeds if you treat in September since they’re smaller and it takes less weed killer to kill small weeds than mature weeds.