It’s that time of year again….time to think about controlling weeds before they take hold of your lawn or garden. I’ve been so busy that I didn’t get my pre-emergence down as early as I like but late is better than never! If you live further north you still have time to apply your pre-emergent for the best control. Preventing weeds before they make an appearance is the best idea to control weeds. Let’s review the types of weed control.
Chemicals that prevent or kill existing weeds are known as herbicides. While all herbicides control weeds, the key is to know which one is most efficient for your weed problem. First it’s important to properly identify the weed you wish to do away with and understand its growth cycle. This will enable you to choose the proper herbicide product and correctly time its application to achieve best weed control.
Herbicide products can be classified several ways. One is by their activity - selective or non-selective. Generally most herbicides are selective, meaning they will only control specific weed species without damage to nearby grasses and ornamentals. When controlling weeds in lawns, it is also important to know your variety of turf grass, since their tolerance to herbicides does vary.
Non-selective herbicides will kill or damage all vegetation, so it is important to apply them precisely to avoid injuring desirable plants and grasses. These are commonly used in landscaping for lawn renovation and for controlling weeds and brush along highways.
Another classification for herbicides is based on the time they are applied in the weed's life cycle. Pre-emergence herbicides are most effective when applied a few weeks prior to the germination and emergence of weed seeds. They will not control established weeds. These herbicides create a weed control zone on the soil surface, preventing seeds from germinating. Because most pre-emergents have a long residual, they are not recommended for newly seeded turf grass. Annual weeds such as crabgrass, annual bluegrass and goose grass are normally controlled by pre-emergence herbicides.
Post-emergence herbicides are applied after the weed is established and actively growing. While a some products work through soil application, most of post-emergents work on contact. They are absorbed through the surface of leaves and translocated throughout the plant. It is recommended that applications be made during a dry, eight-hour period, since rain can wash off the material and lessen control. Most broadleaf weeds are controlled by post-emergent herbicides.
Remember before you buy and apply any herbicide, carefully read the entire label for exact weed species controlled and places where it can be safely used. It is important to review precautionary information and restrictions, follow directions for use, and store and dispose of empty containers as indicated on the label. Unfortunately some people feel that is a little product is good, a lot will be even better. This is not true and can be very harmful to you, your lawn and the environment.
If you don’t want to use any chemicals you can always pull or hoe your weeds. When using this method remember to start early to stay ahead of the weeds!