Can A String Trimmer Cut Weeds?

No one wants to come across weeds growing haywire on their lawn or garden, and as soon as you see one, there’s no doubt you will want it gone. If you only have a string trimmer at home, it’s understandable if you are wondering if a string trimmer can be used for this purpose.

While a string trimmer will undoubtedly be able to carry out the physical act of cutting weeds, this is not a recommended action. The reason for this is cutting weeds may cause debris to fly all over the garden – which can include seeds. The outcome may be that you will end up with a lot more weed growth than you started with.

Understanding what tools work best on what kind of growth in your garden is crucial to get the right look for your backyard. In this article, we will discuss whether or not you should use a string trimmer to cut weeds and why, and more about your string trimmer! Keep reading to find out!

Should A String Trimmer Be Used to Cut Weeds?

String trimmers are handy garden tools that allow you to clean up hard-to-reach areas. For this reason, many home gardeners may think it is the best tool to get rid of weeds growing just out of reach of any other tool. Using a string trimmer for such a purpose makes sense in theory, but in practice, it may cause a lot of harm in the long run.

The reasoning behind this is that a string trimmer, when cutting grass, causes all the debris and cut-up pieces to fly around it, across a large space of the area. 

This is fine when cutting grass because you can always clean up afterward, and there is no real harm. However, when weeds are involved, there is one thing that can be severely detrimental to your garden: seeds.

If you cut up weeds using a string trimmer, you can send a lot of seeds flying out all over the garden. Because your garden will usually be getting plenty of water and care, there is a good chance these seeds will germinate and spread. In fact, you may end up with far more weeds than you did when you started the process of cutting the plants out.

Another issue with using a string trimmer in weed eradication is that a string trimmer tends to cut the grass to a shorter height. As a result, more sunlight can reach the soil, which will help any new weed plants grow faster and more effectively. This can leave your garden more prone to further growths you do not want.

This is why using a string trimmer is absolutely not recommended to get rid of weeds. Instead, you can always try using a weed cutter for a quick and effective cut that helps you remove both the plant and any prospective seeds. For the most cautious approach, you can pull the weed out by hand as long as you remove the roots with the whole plant.

Of course, this can be time-consuming but it will result in less work in the long run. 

When Should You Use a Trimmer to Cut Weeds? 

While generally using a string trimmer to get rid of weeds is best avoided, you can try using the device in certain circumstances. For example, if you are certain you are cutting a plant that has not yet produced seeds, you can try using a string trimmer to get rid of it.

Another scenario to consider is if you are using other measures to prevent weed growth in the future, and just need to get rid of an eyesore, you can still use the trimmer to get rid of weeds, but you should keep in mind you will need to have the right string trimmer line to get results.

What Size Should a String Trimmer Line be for Cutting Weeds? 

If you absolutely have to use a string trimmer to cut weeds, you need to have the correct line size. String trimmer lines are available in multiple sizes, ranging from 0.065″ to 0.110″ or higher. 

What size works best will depend on which area of the garden you’re using the string trimmer. For example, line sizes like 0.065″ to 0.085″ works pretty well for light work like cutting grass.

If you’re using the string trimmer for weeds or thicker grass, you may want to get a line sized between 0.085″ to 0.110″, as this will allow the machine to grasp onto the thicker weeds and remove them better than the smaller line sizes.

Similarly, the line material and shape also depend on your needs. You can go for nylon strings as they are strong. For the line shape, you’ll find several options as well. Select the best one according to your application. 

The table below shows the different diameters and line shapes for string trimmers. 

String Trimmer Line Weight/Diameter String Trimmer Line Shapes
Light – 0.065 to 0.080 inch Round Trimmer Line
Medium – 0.080 to 0.110 inch Twisted Trimmer Line
Heavy – 0.110 inches and higher Squared Trimmer Line
  Multi-sided Trimmer Line
  Serrated Trimmer Line

If you are unsure about what trimmer line you need for the task ahead, you should check out this article I wrote about choosing a trimmer line


Can I use a hedge trimmer to get rid of weeds?

Yes, you can technically use a hedge trimmer to get rid of weeds. However, this may not be the most efficient method to achieve this, and you may have to deal with repopulation in the future.

What is the best way to completely get rid of weeds?

While machines like the string trimmer or a hedge trimmer can help you remove weeds, they are not the best way to eradicate them from your garden. In fact, the best way to do so is to use a hands-on approach and remove all weeds, along with the roots, from your garden before they produce seeds.

Final Thoughts

Using a string trimmer to get rid of weeds may seem like a quick and easy solution, but it often can cause more harm than good in the long run. It is best to avoid this method unless you are certain the plant has not produced seeds, or if you have other measures in place to prevent weed growth. 

And remember to always use the correct size and shape of the trimmer line for the job. Overall, using a more hands-on approach to removing weeds is often the most effective solution.

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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