If you have a yard, you know the constant struggle to keep weeds at bay. The little suckers can pop up in the most surprising places too. Usually, you have two methods of disposing of the weeds: chemical herbicides or manually pulling them.
Manually pulling weeds is a great eco-friendly way of dealing with weeds and typically produces the best results. However, it is time-consuming and labor-intensive. Manually pulling weeds is not a good solution if you have lots of weeds or need to cover a larger area.
Chemical herbicides are very convenient. Essentially, you can just spray and walk away. However, commercially available weed killers have nasty chemicals (glyphosate, 2,4-D, dicamba) that can cause pollution and pose health risks for people, pets, and other animals. There’s also some evidence they may contribute to weed resistance.
An excellent alternative to these methods is my eco-friendly $5 DIY Weed Killer, but there are some circumstances when that’s not the right solution. The DIY Weed Killer mix contains salt, which is not great for soil health if you plan to plant other plants in the same spot after killing the weeds. That’s where the $0 DIY Weed Killer: Eco-Friendly Boiling Water Method comes in!
What Makes Boiling Water Effective Against Weeds?
Boiling water kills weeds essentially the same way it kills germs and just about anything else you pour it on. The high temperature of the boiling water causes instant thermal shock to the plant, causing massive cell death. If you use enough boiling water and get enough coverage on the plant, especially down to the roots, you can kill the entire weed with just boiling water.
What Weeds Is the Boiling Water Method Good For?
Boiling water is especially effective for smaller weeds and weeds with shallow root systems. Annual weeds like chickweed and crabgrass are great candidates. However, boiling water will be less effective on perennials with deep roots, like dandelions, and might require repeated treatments.
Benefits of Using Boiling Water to Kill Weeds
Cost-Effective
Since this method only requires water and a heat source, it’s practically free. Sure, there is a nominal cost for the water and the energy to heat it, but it will be cheaper than flushing the toilet or doing a load of dishes in most cases. And since you can make this yourself with what you have at home, you essentially have a limitless supply of DIY weed killer!
Eco-Friendly
Since this uses only clean, potable (and dangerously hot) water, you are not introducing chemical pollutants to your soil. You could argue that boiling water will kill some beneficial soil bacteria, but this should be limited to the treatment area and isn’t likely to negatively affect your overall soil health.
Non-Toxic
After treatment, there are no lingering dangerous chemicals in your yard. So you do not need to worry about your goofball dog rolling around in herbicide or your kids ingesting anything toxic.
Immediate Results
Most weeds will show signs of wilting and death within 24-48 hours. Though, in my experience, that can vary. I’ve seen small weeds shrivel up upon contact with the boiling water, and some larger weeds take a few days to die. On the plus side, it’s pretty easy to whip up another kettle of boiling water and get those suckers gone!
How to Safely Use Boiling Water for Weed Control
Equipment Needed
- Electric Kettle with a spout for precise pouring
- Protective clothing like gloves and shoes to prevent burns
Use an Electric Kettle
You can boil water on the stove with an old-fashioned kettle, which will work just fine for killing weeds, but it will take a lot longer and a lot more hassle. Instead, invest in an electric kettle. You fill it with water, flip a switch, and in a few minutes, you have a kettle full of boiling water ready to fry up some pesty little weeds. A kettleful of water pours out quicker than you might think, so you’ll be glad you got the electric kettle when you have to do 4-5 kettles worth of boiling water. There are many available on Amazon; here’s the electric kettle that I use.
Protect Yourself: Wear Shoes, Pants & Gloves
You’re about to pour some boiling water on the ground, and in case you didn’t know, boiling water can burn the crap out of you. Do yourself a favor and make sure you’re wearing close-toed shoes, long pants, gloves, and maybe even eye protection before doing this. If you’re under 18, don’t do this without adult supervision.
Bring Water to a Full Boil
If you have an electric kettle, as we discussed earlier, you just need to fill it with water and flip a switch. Then, give it a few minutes.
Pour Boiling Water on the Weeds
Carefully pour the boiling-hot water onto the target weeds. You’ll want to cover all visible parts of the plant. Also, get the base where it meets the soil to get the water down to the roots.
Boiling Water Method Results
Before
Here, you can see some healthy little weeds sprouting up in my planter bed.
During
Fry suckers, fry!
After
Here they are a few days later. You can see they are dead/dying.
Before
Here is a big crop of weeds growing in my planter. I didn’t want to use herbicide or my $5 DIY Weed Killer here, as I’d like to grow other plants in this box later.
During
Nice knowing ya, weeds.
After
Here they are a few days later. You can see they are shriveled up and dead.
Fried to a crisp.
Additional Application Tips
- Don’t use near desirable plants, as the boiling water can damage them as well.
- You may need to treat the same area or plant multiple times, especially if it’s particularly resilient or hard to kill.
- Apply during warm, dry weather. The boiling water won’t be as effective if it’s cold and wet outside.
- Consider mulching afterward to prevent new weed growth.
- Combine with my $5 DIY Weed Killer Method for an integrative approach.
Conclusion
As you can see from the before-and-after photos, using boiling water to kill weeds definitely works. It’s cheap, eco-friendly, non-toxic, and very simple to do. Give it a try, and let me know how it works for you! Also, check out my other low-cost DIY weed killer.