7 Reasons Why Weeds Keep Growing Back in Your Lawn

Do you feel like you’re fighting a losing battle against weeds in your lawn? This can be incredibly frustrating, particularly if you feel like you’ve tried everything and nothing is working. The weeds keep on coming.

This is a major problem. Unwanted weeds not only impact the overall aesthetics of your property but they also compete with your healthy, desirable grass for air, water, and nutrients. When too many weeds invade, they can weaken your lawn as a whole.

Of course, there may be many reasons why weeds keep coming back in your lawn, some of which might come back to mistakes that you’re making. Unfortunately, weed control can be more complicated than most people make it out to be. It’s not just a matter of tossing down some weed and feed as a lot of people think. There are actually numerous factors that come into play and can impact whether or not weeds are likely to grow.

Here are some reasons why you can't get rid of weeds in your lawn.

1. You’re Mowing Improperly

A lot of homeowners are surprised to learn how big of an impact mowing can have on their lawn’s health in general. But improper mowing habits can weaken the lawn and make it easier for weeds to grow back. Most notably, when you mow your lawn too short or you scalp the edges around hardscaping, you create conditions that are favorable for weed growth. That’s because opportunistic weeds like crabgrass love thinned out areas of the lawn where it is easy for them to get plenty of sunlight. 

In Northern Virginia, we recommend that you keep mowing height to around 3 ½ or 4 inches. It’s also important that you're careful not to scalp the edges and create areas where weeds will creep in. 

Finally, keep a sharp mower blade and maintain a level mowing deck. When you create jagged cuts (as opposed to clean, crisp ones), you put quite a bit of additional stress on your grass blades. Anything that weakens your lawn will increase the likelihood of weeds.

2. Your Lawn is Underwatered

Drought stress can also increase the chance of weeds growing back. That’s because weeds are better able to take advantage of a struggling lawn. Because water is such a vital element to your lawn’s overall success, a lawn that is underwatered will struggle to grow thick and healthy.

Dying or dead grass can really open your lawn up for weed infiltration and things will only go downhill from there. Weed control for lawns is not very effective when the lawn’s health is severely struggling.

Fortunately, watering your lawn more regularly can prevent weeds from coming back. During its active growing season, your lawn should be receiving around 2 inches of water each week. If you aren’t getting that amount in rain, it is critical that you water your lawn manually or consider an irrigation system to make up for what’s missing.

3. Your Soil Health is Out of Whack

Most people don’t realize just how important their soil is to their lawn’s overall health. But when your lawn’s soil health is struggling, it’s impossible for your lawn to perform optimally. 

Healthy soil is thriving with beneficial microorganisms like beneficial fungi and bacteria, which help your lawn to take advantage of the nutrients found natively in the soil (as well as those provided by added fertilizers). But when soil is in poor shape, the lawn as a whole will struggle.

Fortunately, there are solutions for pool soil health but first, you need to know exactly what is wrong. This is where lawn soil testing can make a huge difference. At Turf's Up, we include soil tests in all of our lawn care programs because we understand the importance. Without knowing exactly what’s going on in your soil, problems can’t be fixed.

One of the common soil problems may be its pH. While healthy grass will struggle to grow in lower pH soils, some weeds actually prefer it. That means you could have soil that is better-suited to weed growth than grass growth! Figuring out whether you might be dealing with a soil pH problem is important so that effective correction steps can be taken. This circles back to the value of a lawn soil test.

4. Your Soil is Compacted

Soil compaction is another soil problem that could be impacting its overall health. This is also a reason why your grass may not be growing well and weeds might be invading. While healthy grass will struggle to grow in compacted soil, certain weeds have adapted to grow in these conditions. 

It’s also important to recognize that compacted soil can make it difficult for lawn care care products to penetrate the surface. Unfortunately, these products aren’t going to do much good sitting atop your soil.

The answer to compacted soil is lawn aeration, seeding, and topdressing.

Aeration is a service in which a core aeration machine is used to make small holes in the soil by pulling “cores.” These are then left atop of the soil to infiltrate back into it, loosening the soil as it does. This also allows more water, oxygen, and nutrients to penetrate the soil and get down to the root zone, where they are needed most.

Seeding is best performed immediately after aeration when the seeds can fall into the holes that were created in the lawn, providing the best seed-to-soil contact. Finally, to give your lawn the best chance at optimal performance, topdressing with compost can also be performed. As compost falls into the holes made during aeration, it will mix with the clay and help create a better layer of topsoil by improving soil structure and microbial life. This goes back to the importance of optimal soil health.

5. Your Lawn Has Too Much Shade

If your lawn is not receiving enough sunlight, it’s never going to perform optimally. Grass needs around 5 to 7 hours of direct sunlight each day to grow and thrive. Of course, there are plenty of weeds that have adapted to shady growing conditions. For instance, ground ivy has been known to pop up in shaded areas of the lawn and can spread rapidly.

If you have a shady lawn, you might need to look into tree pruning or even removing them entirely so that your lawn can get more sunlight. This will help your grass to grow thick and healthy and naturally choke out weeds.

If you don’t want to remove your trees and value that shade, you might need to consider alternative solutions to a lawn in particularly shady areas. Adding some flower beds with shade-loving plants or extending tree mulch rings can be effective solutions if you cannot get grass to grow thick and healthy in these spots.

6. Your Lawn is Sick (Due to Disease or Pests)

We’ve already discussed how an unhealthy lawn can be more prone to weed growth as a naturally thick lawn will help prevent weeds from growing back. As we’ve mentioned, your lawn could be thin and struggling due to mowing problems, soil health, lack of sunlight, or lack of water.

But your lawn could also be thin and struggling because of a disease or pest problem—and this will also make weeds more likely to invade.

Patches of brown and dying grass are commonly caused by turf diseases such as Brown Patch of Dollar Spot. While some fungal diseases are due to temporary environmental conditions and will resolve themselves when the weather improves, a bad case of turf disease may require a fungicide.

Pest problems can also wreak havoc on your turf’s overall health. Insects, such as grubs (which are the larvae of beetles like the Japanese beetle) and chinch bugs can feed on your lawn and cause it to die. You can be sure that opportunistic weeds are going to take advantage of a lawn struggling with pest problems.

7. Your Weed Control Services are Flawed

Even if you feel like you’re tackling weed control with various products or services—or maybe you’ve even hired a pro to handle weeds for you—not all weed control services are created equally.

For one, you (or your lawn care company) may not be using the best weed control products. The simple fact is that not all weed control products are the same quality. Some more expensive products are going to be more effective. But not every company invests in high-quality products. If you’re performing DIY weed control, you won’t even have access to the best products. You’ll be limited to what you can purchase at a big box store. 

Another reason that weed control methods may be flawed is that the approach is not varied. Getting rid of weeds is more complex than using one type of product to cover everything. To best get rid of weeds, you need to make sure that you are using the right products on the right weeds. Some hard-to-control weeds are even going to require specialty controls.

Along with that, the timing of when you spray for weeds as well as how often you spray can also impact your success. Whether you’re taking a DIY approach or you’ve hired a pro, if you’re not switching up your products and approaches, you’re not going to have the best results.

Effective Weed Control for Lawns in Northern Virginia

As you can see, weed control for lawns is quite a bit more complex than most people realize. There are just so many different factors that can come into play and have an impact on your overall success (or failure).

The truth is, there is no one single “best method” or answer to preventing lawn weeds. It comes down to a comprehensive approach incorporating both optimal lawn care and weed control. 

With lawn care, you want to be sure you’re utilizing a multi-faceted program that includes good habits like lawn aeration, overseeding, topdressing, regular watering, proper mowing, and the nurturing of good soil health. In addition, you also want weed control services that utilize the best products and approaches in order to tackle even the toughest-to-control weed varieties.

With a multi-faceted effort like this, you can finally start to see some success.

Of course, this isn’t easily achieved on your own or with a company that cuts corners. In order to truly have the best success, you need to partner with a company that will create a customized and multi-faceted plan that will help you win the battle against weeds.

If you’re ready to start seeing fewer weeds and an overall healthier lawn at your Ashburn, Aldie, or Leesburg, VA home, talk to an expert, choose a solution, and get ready to see the results you desire.