Skip to Content

How to Make Homemade Weed Killer

If you’re tired of spending too much money on expensive weed killers that you have to constantly re-apply, then this post is for you!

Keeping weeds at bay is important for growing a thriving garden. To ensure a wonderful harvest, don’t let expensive weed killers deter you from keeping your garden clean and weed-free!

Continue reading to learn how to make homemade weed killers, the purpose of each ingredient, and the best techniques for applying them.

Using a garden sprayer to spray weeds growing in between sidewalk and brick wall.

Why Make Your Own Weed Killer

There are many advantages to making homemade weed killers. For starters, it’s much more affordable than purchasing a commercial weed killer from a big box store.

Another advantage is knowing the ingredients you’re using in your yard. When making your own weed killer, you can customize it to fit your needs. If you see that something isn’t dying as quickly as you’d like, or there’s a specific plant you don’t want harmed, you can adjust your weed killer to meet your expectations.

Importance of Reading Labels and Knowing Ingredients

Chances are your backyard is where the most important people in your life like to hang out and play. Whether it’s your spouse and kids or your favorite pet, it’s important that you know what you’re putting on your lawn and if it can harm those you cherish most.

Most commercial weed killers have harmful ingredients that can poison pets and children if exposed to large amounts. When you make your own weed killer, you can control what goes into it and what your loved ones are exposed to.

Price Comparison

Whether you choose a homemade weed-killer recipe that has just a few ingredients or many, there’s a large chance you have all of the ingredients at home already. If not, they can be found at your local supermarket for just a few bucks per ingredient.

If you’ve been to your local garden store lately, you may have experienced sticker shock when you looked at weed killer’s prices. A gallon of commercial-grade weed killer can cost upwards of $60!

Vinegar Weed Killer

Bottle of white vinegar, one method for how to make homemade weed killer.

One of the most common homemade weed killer solutions is vinegar weed killer. This simple mixture has only four ingredients and kills most broadleaf weeds. Broadleaf weeds have netlike veins in their leaves. Common broadleaf weeds are chickweed, dandelion, and thistle.

For directions and more information, take a look at our post on How to Kill Weeds with Vinegar.

Boiling Water

A tea kettle steaming on a stove burner.

You may be surprised to learn that boiling water is another way to kill weeds at home. Using boiling water gives quick results as the plant goes into shock when the water is applied. After a day or two you’ll notice the plant withering and eventually dying.

This method works best on young weeds and in walkways and patios with small cracks.

Rubbing Alcohol Solution

A generic bottle labeled as rubbing alcohol.

Making homemade weed killers with rubbing alcohol is most effective on hot, sunny days. The sunshine helps to dry the alcohol, which draws the moisture out of the weed, causing it to become weak, dry out, and die.

This rubbing alcohol solution is easy to make — you dilute two tablespoons of rubbing alcohol in four cups of water. Once diluted, transfer to a spray bottle and begin killing weeds!

Borax

A box of 20 Mule Team Borax, a powdered deterrent booster product.

Borax is a great option when looking for chemical-free weed killers. Because of its efficacy, adding any ingredients to the Borax and water solution is unnecessary. It is important to remember that Borax is non-selective, which means it will kill any plant it comes into contact with. Be careful when applying so you don’t accidentally harm something you’ve planted.

As mentioned above, this weed killer is simply Borax and water. Since Borax is a powder, you must dissolve ten ounces of Borax in four ounces of warm water. Once dissolved, dump into two and a half gallons of water and mix well. This two and a half gallons of Borax weed-killing solution can treat up to 1,000 square feet.

The Controversy Over Corn Gluten Meal

Corn gluten meal.

There’s debate in the agricultural world about the use and effectiveness of corn gluten meal as a pre-emergent herbicide. To be clear, this is not the corn meal products you’ll find on your grocery store shelves and there are a lot of “corn meal myths” circulating about sprinkling this around plants or in your lawn to prevent weed seeds from germinating.

Corn gluten meal is a specific product that is marketed for herbicide use. It’s a corn byproduct that has been processed to create a coarse grain containing 10% nitrogen. The dipeptides found in corn gluten meal are credited for preventing seed germination of all kinds, so this is applied only after desirable seeds have germinated but before weeds emerge.

This isn’t a recommended homemade weed killer for several reasons. The first is that corn gluten meal is expensive. Secondly, it has to be applied at 20 pounds per 1,000 square feet. This means two pounds of nitrogen per 1,000 square feet — nitrogen gets converted into nitrates, which you don’t want getting into groundwater.

Finally, the studies are inconclusive as to whether or not corn gluten meal does what the claims say it does. Researchers in Oregon and California couldn’t replicate the findings of other corn gluten meal herbicide studies.

So save yourself some money and keep the groundwater in your area safe by skipping this natural weed-killer method.


Techniques for Applying Homemade Weed Killer

Just like there are many ways to make homemade weed killer, there are also many ways to apply it. Each method is different, and you want to be well-versed in your different application options to ensure the best results.

Paintbrush Method

The paintbrush method is a great option if the weeds you need to tend to are among other plants you want to keep. Simply pour your homemade weed killer into a cup and use a paintbrush to carefully paint the solution onto the vegetation that you want to get rid of.

It’s important to remember to paint the entire plant down to the roots to increase the probability that you won’t have to re-apply in a few days.

Spray Bottle

A handheld spray bottle is another simple way to treat weeds with homemade weed killer. When using a spray bottle, you may need to adjust the spray range to ensure that you don’t have overspray landing on plants you want to keep alive.

Applying homemade weed killer with a spray bottle allows for even distribution; it’s much less time-consuming than the paintbrush method.

Pump Sprayer

A pump sprayer works best for large areas like a parking lot or driveway. Oftentimes these come with a strap to wear as a backpack or on a trailer to pull behind your tractor. They hold larger amounts of homemade weed killer, and their sprayer targets a much larger area than the spray bottle.

If you choose to use a pump sprayer, remember that homemade weed killers lose their potency if left to sit for multiple days. To keep waste down, don’t fill your pump sprayer with a weed-killing solution and assume you can leave the rest inside to use later.


Best Time of Day & Weather to Kill Weeds

The very best time of day to kill weeds is midday when the sunshine is its hottest, and the dew has dried up. The drier and hotter it is, the more effective your homemade weed killer is.

Keeping an eye on the forecast is vital. You will want to give your weed-killing solution at least two hours to dry before a rainfall.

When to Re-Apply

If you aren’t seeing a change in the look of the weeds you’re trying to kill in 2-3 days, you may need to re-apply weed killer. This doesn’t necessarily mean that the weed-killing solution you made isn’t any good. There are a couple of things to consider:

First, was enough weed killer applied to the vegetation, and did it reach the roots? If you only applied to the top of the plant and the roots remained unaffected, chances are you’ll need to re-apply. It’s always important to make sure that the base of the plant is coated so that the roots receive weed killer.

How was the weather after the first application? Even the slightest sprinkle can wash the weed killer off, leaving the weeds unaffected. It is so important always to check the forecast!

Lastly, if the factors above have been considered, you may need to increase the potency of your homemade weed killer. Increase the amount of the main ingredients and decrease the amount of water you use when mixing the weed killer. This is one of the many perks of making homemade weed killer!


Give Homemade Weed Killer a Try!

Person wearing protective gloves for spraying herbicide.

As you’ve read, there are many advantages to making homemade weed killer, from personalizing it to fitting your yard’s needs to ensuring you’re giving your loved ones a safe place to play. Whatever your reasoning, we hope you’ll try making your own homemade weed killer this summer!

If you feel like you need to learn more about these pesky garden tenants, check out our weeds page to learn all about different weed varieties, treatment options, and surprising information.