Understanding Pre-emergent vs. Post-emergent Weed Control

Weeds are the enemy of a healthy and thriving lawn. Nobody likes finding weeds growing as they can detract from the overall look of the lawn. Weeds can even begin to compete with your healthy turf, making it more challenging for your grass to grow and thrive.

If you’re on a mission to get rid of weeds, you might be wondering the best way to deal with them.

While most people recognize that weeds can be an almost year-round problem, they don’t always realize that means their control approach needs to be varied. Different weeds require different solutions—at different times of the year! There’s a lot more involved in weed control than homeowners tend to realize. And when something isn’t working, it’s often that they need a different solution.

In this article, we’ll talk about pre-emergent vs. post-emergent weed control, including what some of the differences are and when these different approaches are warranted.

When it comes to fighting some of the tough weeds found in our area, you need to take a comprehensive approach.

The Difference Between Pre-Emergent and Post-Emergent Weed Control

Weed control products can be broken down into two primary categories: Pre-emergent or post-emergent weed control.

While pre-emergent weed controls work by preventing weeds from germinating in the first place, post-emergent weed controls kill weeds that have already come out of the ground.

Unfortunately, no pre-emergent products work on all varieties of weed. But they do work with specific weed types like crabgrass. Because crabgrass is such an invasive (and also prevalent) weed in our region, crabgrass pre-emergent products (also sometimes called “crabgrass preventer”) are a vital part of a lawn care program.

crabgrass along edge of driveway

Crabgrass preventer works by forming a barrier near the surface of the lawn, which will intercept the germinating crabgrass seeds before they even have a chance to grow. This will prevent the majority of crabgrass from growing in the first place.

As you might have guessed, there is a limited window when pre-emergent controls can be used. Since these products work by preventing germination, they must be put down in early spring prior to germination. The optimal timing for application is dependent upon soil temperatures.

technician lawn spraying with weed control

Although pre-emergent products are effective for preventing around 80 percent of crabgrass growth, breakthroughs can occur (especially in thinned-out areas of the lawn, where it may already be struggling).

This is why post-emergent products are also so important. Some weeds can also only be treated with post-emergent products after they’ve already grown. So, it’s important that your lawn care program is not solely reliant on pre-emergents.

A Word on Liquid vs. Granular Weed Control

In general, weed control products are available in both liquid and granular forms but what’s best often depends on the exact scenario that you are dealing with.

granular fertilizer sprays out of walk behind spreader

In many cases, we have found that liquid is best for any post-emergent control that is required as it provides better coverage of leaf tissues. But granular pre-emergents are best when it comes to treating crabgrass.

Your lawn care technician should be able to make the right choice between liquid or granular when the situation calls for it.

Weed Control is More Than Pre-Emergent vs. Post-Emergent Herbicide Decisions

There is no question that knowing when to use pre-emergent vs. post-emergent weed control is important. But due to the wide variety of weeds found in our area, a thorough weed control program must go further than that.

The truth is, weed control is more than just targeting weeds with products.

You want a lawn care service that also focuses on good soil health with products like fertilizer and bio-stimulants that help grow a thick lawn. That’s because a thick lawn is a natural defense against weeds. A company that also performs services like soil testing and resulting limestone application is also beneficial since certain weeds thrive in low pH soil.

Sometimes, the weed control arsenal also needs some updating or rotation. It’s not uncommon for homeowners or even some lawn care companies to use the same products again and again. But as you can already tell, a successful weed control approach needs to be varied.

Using the same control product year-round is simply not effective as some products are better for certain points of the season. Temperature absolutely has an impact on product effectiveness and experts will be keeping up with changes in temperature and what products will work best for those changes.

There are also weeds, like nutsedge, that require specialty controls. Nutsedge can sometimes require more than one application since it is so aggressive.

A successful lawn care service could also use “sticker products” for tougher to control weeds. Some weeds are better controlled with an additive mixed into the product that allows it to “stick” to the waxy leaves rather than just running off.

lawn aeration machine aerates lawn at home

In general, a lawn care program that promotes a healthy lawn will also make a difference in your weed control efforts. This includes services that will promote the thickness of your lawn, like fertilization and aeration and overseeding.

Aeration, which is the process of pulling small cores of soil throughout your lawn, allows more oxygen, water, and nutrients to penetrate deep into the soil and down to the root zone. This is best done at the time of seeding in order to give your grass seeds the best chance at germination.

When you take steps to thicken up your lawn, it makes it more difficult for weeds to grow and thrive.

Working with a Lawn Care Company that Takes Weeds Seriously

As you can tell, pre-emergent or post-emergent weed control is just one decision when it comes to an effective weed control program. Ultimately, you want to choose a lawn care company that is going to take this seriously and help you get the best results.

When you spend time outdoors, you shouldn’t have to worry about weeds. You should be able to enjoy your time outside rather than being stressed or burdened by the site of unwanted weeds.

That’s why making the best control choices is so important.

Ultimately, you want to choose a company that not only has a comprehensive weed control program (using different methods at different times of the year) but also has a full lawn care program. By promoting a thick and healthy lawn, you can begin to naturally choke out weeds.

While weeds can be a major nuisance, with the right approach to weed control, you can be on your way to getting rid of them and getting back to enjoying your lawn to the fullest!

If you’re wondering how to deal with weeds, or any other question for that matter, we are happy to be a resource. We want to your Allentown, Bethlehem, or Easton, PA lawn to be dark green and healthy. Get in touch with us to get some free expert advice and learn more about our lawn care programs which include three lawn care pricing options.

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