Know When to Apply Herbicides
Now that you understand a little more about the active ingredients in weed control products, it's good to also review the timing of herbicide applications. This will help you get the most bang for your buck while providing the control you expect.
You want to control weeds while they are young. Mature weeds are very resistant to herbicides and you will only have limited success going after them.
Fall is the very best time to control broadleaf weeds such as dandelions because this is when they germinate. For a lawn with fewer dandelions in spring, kill them when they are most susceptible. Time your herbicide application for a fall day around the time of the first frost in your area, or when the night time temperature has at least dipped to 40°F.
If you missed your fall application and dandelions and other broadleaf weeds drive you crazy in spring, you can achieve limited control by applying herbicide a couple of weeks after the dandelions fluffy seed pods have matured. The plant will be more susceptible to the herbicide at this time. This herbicide application gives you the added benefit of killing other weeds that have flowered as well as some summer annual weeds that are just beginning to germinate.
Spring is the time to control annual grassy weeds like crabgrass and foxtail. This is when they germinate and you want to clobber them while they are young. The best method is to apply a pre-emergence herbicide in the early spring before the soil temperature rises above 55°F. If you miss this window, post-emergence herbicides in early summer are your second-best bet.
A weed control program, along with fertilizing and proper mowing, will soon turn your lawn into the envy of the neighborhood.
