Nothing is more important to the value of your home than the first impression potential buyers get when they pull up in front of your house. A lush green lawn welcomes you and your guests and is an asset not only to your neighborhood, but adds curb appeal and value to your home.
You spend a lot of time keeping your lawn and yard looking great, but no matter what you do, weeds pop up. It’s inevitable. Unless you’ve got a protective dome over it, weed seeds will invade your lawn. They’re wafted in on the wind, deposited by birds flying over, and tracked in with foot traffic of the human or canine kind.
What to do? The answer is to apply pre-emergent lawn herbicides before they have a chance to germinate. Fall is one good time to do this (early spring is the other) because weeds, like most plants, are busy absorbing energy in the fall to build strong root systems for over-wintering. Stopping that process now will save you time and money when everything beautiful comes into bloom.
A pre-emergent herbicide works in the top layer of soil where seeds lie in wait to sprout. Untreated seeds can remain viable for as long as years, but the herbicide will deactivate them permanently. The only issue is that while the herbicide remains effective in the soil for up to several months, new seeds are always finding their way to your lawn.
That’s why a second yearly application is often called for, with occasional intermediate measures like post-emergent spot treatments. The good news is that if you use a pre-emergent herbicide on schedule, every year there will be fewer and fewer weeds marring your beautiful lawn.
The Essentials of Using a Pre-Emergent
Here are the basic steps of treating your lawn to prevent weeds:
- Do it on time. Consult with your local garden center to find out the right time to use a pre-emergent in your region, and don’t wait to apply it. A pre-emergent has no effect at all on weeds that have already begun sprouting.
- Don’t plant new grass while the pre-emergent is active. Most pre-emergents are non-selective, meaning that they’ll kill any seeds that come into contact with, including grass seeds.
- Apply the herbicide evenly, making sure all areas of your lawn are treated. For granular products, an inexpensive hand-held spreader will do the job if your lawn isn’t huge. But use one that drops rather than broadcasts the product to avoid having it fly off into areas of your garden where you don’t want to stop seeds from growing. If you use a liquid product, be careful not to spray anywhere other than the lawn.
- Water the herbicide into the soil per directions. It’s only effective if it’s in contact with the seeds.
- Don’t disturb the surface of the soil. The pre-emergent forms a barrier that is broken if you rake or dig into the soil. Try to keep dogs off the lawn, and be mindful that gophers, moles, and other critters can also destroy the pre-emergent’s protective barrier.
Facts About Weeds
There are two general kinds of weeds. Here’s some information about them that you probably didn’t know:
Annual weeds. These weeds don’t survive from year to year, but can emerge when pre-emergents aren’t active and, unfortunately, can be resistant to post-emergent herbicides. Sometimes hand-pulling them is the only thing to do. The only good thing about annual weeds is that they may be a nuisance in warm weather, but they die off as soon as the temperatures start cooling.
Perennial weeds. These weeds, like dandelions for example, are the hardest to deal with because they can survive and reproduce even in poor conditions due to their reliance on deep, large roots or runners. Perennial grassy weeds are the most difficult problem because their species are quite a bit like lawn grass species, and some varieties are actually desirable as turf in some locations… just not in a lawn that’s intended to be another kind of grass.
Deceptive weeds. This isn’t really a category, but some people aren’t aware that some weeds masquerade as pretty flowers but can do real damage to lawns if they’re left in place and have free rein to take over. Along with the charming dandelion, other other weeds you might be inclined not to treat include white clover, oxalis, wild violet, and creeping Charlie, which is also known as ground ivy, cats foot, field balm, and run-away-robin.
An important step in controlling weeds, whether with pre-emergent or post-emergent methods, is to know what kinds you’ve got growing in your own lawn. For a guide to identifying weeds in your lawn and garden, garden.org has helpful descriptions and photographs.