Contributed by: Mallory Kelley, Regional Extension Agent
A weed can have many definitions, but its true definition is “a plant out of place” and in the case of your lawn, those plants can be hard to control and definitely an eye sore. Some even can be out right painful in the case of the lawn burweed. When looking for control, the product label is the best source of information as to which lawn grasses can be treated with a particular product. Read the label carefully before purchase and use the information to ensure safety to the applicator as well as the home lawn setting.
Quickly, let’s review a few terms that will help you when trying to control weeds in your turfgrass: Preemergence herbicide: A herbicide that is applied to the lawn grass surface before problem weed seeds germinate and emerge from the ground. These herbicides must be applied before a weed problem is even noticed. Postemergence herbicide: A herbicide that is applied after weeds have emerged, but while they are small and actively growing. This type of herbicide is applied to the leaf and stem tissue of the problem weeds. Generally, postemergence herbicides will not control weeds that germinate and emerge after the application. Non-selective herbicide: A herbicide that kills all vegetation treated. Typically, these products are applied to the foliage of the weeds. This type herbicide will also severely injure or kill desirable plants. “Green-up” period (transition period): A short period of time in the spring when desirable lawn grass is emerging from its dormant state. It is dur
ing this time that grasses are most sensitive to herbicides and, in many cases, the herbicide labels prohibit their use.
This year is going to be tricky when it comes to weed control in the lawn due to the crazy fluctuations of temperatures and the fact that we have barely experienced winter. Our turf grasses went dormant, but many of them have been trying to come out of dormancy or “green-up” for weeks now. Generally, I would say February is the time to put out your pre-emergence products to control your spring weeds, but with the February we had, that would not have been a good idea and now March is upon us.
So this year I say skip your winter pre-emergence application, and if you currently have weeds popping up you could spot spray with a non-selective herbicide if your extremely careful or use a labeled post-emergence product so you do not damage your turf. Then once your grass has fully emerged from dormancy apply a pre-emergence that will then help control your summer weed seeds that are sitting there waiting for the right temperatures to germinate.
Knowing what type of turfgrass you have is especially important when it comes to weed control. If you are not sure, you can always contact your local county extension office. Below is a link to the Homeowner Lawn Weed Control Manual that will be extremely helpful in choosing what product is right for you.
When using Herbicides-Always read and follow label directions.
If you have questions on a garden related topic, the Master Gardener Helpline is open!
March through August the Alabama Cooperative Extension System offers a Gardening Helpline for the general public each Monday through Thursday from 9:00 a.m. until 1:00 p.m. This helpline is operated by Master Gardener Volunteers who use research based information to best answer all of your gardening questions.
Join us for a Gardening Lunch and Learn!
Interested in learning more about seasonal gardening topics? Please join us for the FREE Master Gardener Lunch and Learn Program in your area EVERY MONTH from 12:00-1:00, Bring a Sack Lunch, Drinks Provided. Call your local county office for topics, dates and locations for Elmore, Autauga and Montgomery Counties.