6 Reasons You Can't Kill Weeds In Your Lawn - Backyard Boss
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6 Reasons You Can’t Kill Weeds In Your Lawn

Weeds are an incredibly frustrating part of gardening. This is especially true when you think you’re doing everything right and they still rear their ugly heads in between your tomato plants and blooming florals. While properly removing weeds takes patience, there may be a few things standing in between you and the garden of your dreams.

Below, you’ll find six potential reasons that you can’t kill weeds in your lawn and garden. You’ll also find tips for fixing the issues so you can enjoy that outdoor oasis as soon as possible!

Using Weed Killer Incorrectly

Gardener Spraying House Plant
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With plenty of herbicides on the market and a multitude of weed killers that you can DIY, it can be difficult to know if you’re using weed killer properly. It’s important to ensure you’re following the directions outlined for whichever option you use, mixing and applying as recommended. This also means applying during a certain time of year with consideration of different weather conditions, and even at a specific time of day.

Weed Species

Dandelion weeds
Image credits: Michał Ludwiczak via Pexels

Alongside properly using weed killers, it’s important to determine that you’re using the right solution for the species of weed you’re dealing with! Some weeds, such as creeping Charlie, are incredibly persistent and require a bit more time and attention.

Some weed killers are broad-spectrum, which means they’ll kill any type of plant. Other herbicides are selective, which means they’ll target only specific types of weeds. This means your herbicide may not be working because it’s not suited for the type of weed you have.

As a general rule of thumb, you should aim to remove annual and biennial weeds before they flower because their seeds help them spread. Perennial weeds tend to spread via their root system, so it’s crucial to ensure you remove or kill the entire root system.

Unhealthy Lawn

Lawn with brown patches caused by animal urine
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Keeping your lawn healthy is the best way to keep it safe from weeds, pests, and diseases. Some species of weeds are also an indicator that there is an underlying problem. For example, nut sedge points to overwatering while soil compaction and excess thatch can result in moss growth.

Properly maintaining your lawn will help keep it thick, making it difficult for weeds to take hold.  Of course, avoid overwatering or under-watering your lawn. Grass that is too wet or too dry will encourage weed growth. Also, remember to mow your grass to about 2 to 4 inches tall, depending on the type of grass you have to keep it kempt.

The soil pH can also have a big impact on the health of your lawn. If the soil pH isn’t suitable for the type of grass you have, it won’t get the nutrients it needs. Test your soil’s pH level and nourish the lawn with fertilizer to ensure it remains happy and healthy.

Poor Timing

Summer Rain
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Different weeds germinate at different times of the year, so it’s important to apply the weed killer at the right time. With that said, weeds such as crabgrass require more than one application. While you may be removing mature weeds, weed seeds may be germinating, so it will take a little patience to fully remove them.

The weather can have a big impact on how effective your weed killers are. Drought can cause weeds to develop a waxy layer that slows the absorption of herbicides. Dry conditions can cause the biological processes of the weeds to slow, which will also slow absorption.

It is usually best to apply herbicides after rainfall to ensure the weeds will absorb the weed killer. With that said, rain can wash herbicides away, so it’s important to avoid applying when the weather forecast predicts rain. Most herbicides should be fine if left to absorb at least 30 to 60 minutes before the next rainfall.

Also, mowing your lawn too soon after application can remove the herbicide. As a general rule, it’s best to wait 24 to 48 hours to mow after applying weed killer products. Follow the directions on the herbicide you use, applying as recommended.

Lack of Prevention

Lawn Chemical Treatment
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Treating your lawn preventatively is the best way to keep weeds at bay. If you haven’t implemented any preventative measures in your yard, there’s a good chance that weeds will continue to return.

Laying mulch in your garden beds is a great way to prevent weeds. Essentially, a 3 inch layer of straw, wood chips, or even newspaper will block the light weed seeds require to germinate, effectively stopping them in their path. Mulch also has other benefits, such as maintaining soil moisture.

Pre-emergent herbicides are ideal for protecting your lawn from weeds. They target seeds as they germinate and take root, which should nip the problem in the bud. Also, frequently removing weeds as soon as you notice them will help keep the problem at bay. That is, as long as you are using your weed killer properly!

Not Enough Light

Lawn grass and alternatives with sunshine and trees
Image credits: Larisa-K via Pixabay

While many weeds thrive in partial shade, grass loves sunlight and struggles to grow thick in shaded areas. Try pruning trees that cause shade or switch your turf to a more shade tolerant variety of grass.

If you can’t provide the proper conditions to grow healthy grass, consider one of the many grass alternatives such as creeping thyme or clover. As a bonus, they’re also drought-tolerant and easy to care for!

Have Patience!

Patience is key when it comes to weeding, but it’s important to determine if there’s an issue that is making the process more difficult! Consider trying a few weed removal methods in conjunction with one another, as well as following proper preventative procedures.

Do you have any tips for handling weeds? Share in the comments below!