You’ve probably heard that boiling water kills weeds. It’s one of those tips that floats around—usually mentioned right after vinegar and just before something involving Dawn dish soap.
But does it actually work?
Sort of. On some weeds. In certain places. If you do it right. It won’t touch anything with a deep taproot unless you’re committed to repeat treatments. But for weeds growing in sidewalk cracks or between bricks, it works. Not instantly. Not perfectly. But it works!
This is what happens when you use it—and what to expect if you do.
Table of Contents
Does boiling water kill weeds—yes or no?
Yup. It does. Sort of.
If you pour boiling water on a weed, the leaves collapse like they’ve been caught rolling their eyes in church. They go limp. They shrink to half their size. They eventually go brown and die.
But then? Sometimes they grow back.
Why? Because weeds are petty little things with deep, vengeful roots. Especially the ones with taproots—like dandelions, dock, and plantain. You might have to hit them many times before they finally give up and move on to the great sidewalk crack in the sky.
Pro tip to remember: Use a kettle, not a pot. Kettles are precise. Pots are boiling water wave parks.
How boiling water actually affects weeds
Instant effects on foliage
The moment that scalding water hits the leaves, it's like flipping a switch. The plant cells rupture from the heat.
It’s deeply satisfying. Visually. Emotionally. Spiritually, even.
Impact on roots
Under the surface? Not as dramatic.
Boiling water can damage the crown or top of the taproot if you saturate it enough. But unless you pour a lot, or do it more than once, the deeper root stays alive. It’s just down there. Plotting its comeback.
Weeds with shallow roots though? This works great on them.
Why some weeds bounce back
Taprooted weeds store energy. The moment the top gets damaged, the root kicks into emergency mode. New leaves. New shoots. Like nothing ever happened.
But even taproots only have so much energy. Eventually, if they can’t recharge with new leaves, they die.
The Trick
If you want to kill something like a dandelion with boiling water, here’s how:
Repeat the boiling water treatment 5 or 6 times. Every time you see even a tiny bit of green, pour more boiling water on it. It’s annoying. But it works. Eventually, the root runs out of energy and dies.
When boiling water works best
1 hour later
2 days later
Good Uses :
- Sidewalk cracks
- Between patio stones
- Gravel driveways
- Dry, compacted areas where nothing else grows anyway
These weeds usually don’t have deep roots. One or two treatments and you’re good.
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We'll email you this post, so you can refer to it later.
Terrible Uses:
- Grass – You’ll have dead spots everywhere.
- Garden beds – Risky. Boiling water doesn't discriminate. It’ll kill your kale as fast as your chickweed. Not that anyone’s mourning the kale.
- Dandelions in your lawn – Unless you’re into polka-dotted grass, maybe don’t.
How to use boiling water safely
What you need
- Electric or stovetop kettle
- Long sleeves (trust me)
- Closed shoes (not flip flops, not barefoot, not once, not never)
- A killer instinct
Don’t use a giant pot unless you want to slosh boiling water down your legs. I don’t recommend that. Kettle. Always a kettle.
How much to use & how often
Pour slowly and directly over the weed’s crown. Soak it. Let it sizzle a bit. Walk away. It'll be brown soon.
Come back in a week. If it’s looking perky again, repeat.
Usually takes 2–5 rounds, spaced about a week apart, depending on the type of weed and root. You’re basically wearing the weed down until it taps out.
Avoid splash damage
Be careful near garden beds or anything you don’t want dead. The heat spreads underground a little and can fry the roots of nearby plants.
Aim carefully and pour slowly.
The Results
- 1 hour later – Wilted, floppy, green leaves
- 2 days later – Crispy brown death
- Larger weeds – May need more treatments
- Deep roots – Still alive, but not happy
Pros and cons
The good:
- No chemicals. No danger. No birds growing beaks out of their bellybuttons.
- You’ll see wilting in minutes. Yay!
- You have everything at home to do it right now.
The annoying:
- Doesn’t always kill the root
- Needs repeating
- Kills everything it touches
- A lot of kettle refills if you’re dealing with a big area
What nobody tells you
Seal the cracks
Once the weeds are genuinely dead, sweep up the corpses and fill the gaps with sand or polymeric filler. Otherwise, the cracks are just open invitations for the next round.
Lots of weeds = lots of water
If you're treating a long driveway or entire patio, boiling water gets old fast. Waiting for kettles to boil over and over again is—how do I put this—painfully boring.
Got a big job?
Rent a proper weed steamer. Yes, there is too such a thing. It’ll cover a bigger area much faster.
Anyway. That’s how I spent an afternoon boiling weeds to death.
Dianna
Most entertaining post & comment section I've ever read (and I read a lot online!)....
Thank you for making me smile today, and for all this useful info!
Luv U Karen!
Karen
Thanks Dianna! Welcome to my site. Sometimes I swear. Fair warning. :) ~ karen!
Matt Sommer
Since plants can feel pain: http://www.pri.org/stories/2014-01-09/new-research-plant-intelligence-may-forever-change-how-you-think-about-plants This is horrific! You're boiling them alive! A quick death by Roundup would be more humane. ;-)
bob jinglhimer Shmitt
GEEESSSEEE there is always someone like this... VIETNAM VETS used AGENT ORANGE.. The same company MONSANTO that makes ROUND UP.. And you worry about the plant feeling pain?? Gimmee a break!! Use 5% acid WHITE VINEGAR.. Same thing as Round up.. Unless you think the plant might think it is too sour for it.. GGEEEEEESSSSSEEEEE!!
Jennifer Johnson
I boiled hot water in my tea kettle and poured the boiling water on the weeds in the cracks. Then I put my garden gloves on and pulled on the weeds and they came out right away. I'm glad I googled to find out because I wouldn't have thought of doing this. I'm glad I don't have to use chemicals.
Julie
Haven't tried this since we're having a big windy storm right now, but I just read sprinkling a little baking soda will change the pH of the soil enough to prevent weeds. Or at least the same type of weeds. You could find out what kinds of weeds grow in a very alkaline soil. You may like them better. I tried the vinegar-on-a-hot day which worked great for me, but killed everything within 6-8" of the application, including nearby lawn. I did love the result on my stone patio cracks, though.
Sharron
I use a pump sprayer filled with Vinegar and just a litle (3 gal sprayer) 1T of Lemon Joy and spray the weeds on the patio, if its a hot day that does it alone, if not...I go back with the boiling water that way one treatment does it...LOL
Dani
They sell special blowtorches for weeds at Home Depot - they work like a charm. We just burn the weeds in the patio areas early in the season and were done. Really easy!
Stan
I think what you did was not only kill the weeds but you sanitized the soil. Nothing else will grow their until next season :)
Karen
Stan. - Good. I don't want anything growing there. :) And the truth is, you have to keep soil at the temperature of boiling water for about 20 minutes to sterilize it completely, which the weed treatment doesn't even come close to. ~ k!
Thera
Depending on the foot traffic ie: kids and pets, plain old bleach straight from the bottle, works wonders!
Chau
Oh this is wonderful. Thanks for the tip, Karen. You're the best.
Ruth
*fades into background, and resolves to henceforth be as quiet as a mouse, until our economy is resuscitated*
Ruth
We use gas stoves, for the most part, and since gas prices (and the cost of the alternative... electricity)are at an all time high, I will not be attempting this. There are, however, some 'economically viable' solutions sprinkled in among the rather entertaining comments. :D
Don't you just love being the catalyst for quality entertainment? The 'powers that be' should raise your salary....
Karen
Ruth - That would be you. The powers that be are you. Raise please. ~ karen
Deb Too
My neighbor, a landscaper, told me about boiling water, said it works great. I've yet to try it; I'm still out there scraping, digging, swearing at the weeds between the pavers. Pesticides illegal? Who knew? Of course, I live in Oregon, so wouldn't think of using the stuff...I'd be escorted to the border, I'm sure. (I think people do use it, but only after dark on a moonless night). Regarding the vinegar, neighbor also said to boil it like you would the water (mixed wih water?), but the thought of asphixiating myself trying to get to the stove definitely put me off.
Annie Kip
What an awesome easy idea - thanks!!!!
trisha
i guess i fall in the dirty hippie category, hell i'm even wearing deodorant that i made myself.. so our gardens are definitely 100% organic. but the douchebag that lives next door - thats another story. oh how i wish i could take a picture of what the idiot's yard currently looks like.
i woke up saturday morning to see that his newest adventure in chemicals was spraying his entire edge on both sides of the sidewalk and the walk going up to his house - the curb - around a telephone pole - around a tree stump - yes ALL yellow and dead. the point? maybe he wanted a striped yard? i don't know. but hes an idiot. my mister said, "it's called an EDGER, dumbass"
people just aren't as smart as us karen, plain and simple.
Karen
Agreed. Dirty hippie. ~ karen
Monique
Karen, thanks for this great tip. We've tried the vinegar and baking soda solution but the weeds tend to return. Can't wait to try boiling water on them. I'm guessing that pouring hot water on the weeds after the weeds have been baking out in the hot sun for a day or two, will encourage their demise.
deb
Too weird... I just tidied up my crack this morning! Really! Mix half a gallon distilled vinegar, juice of 1 lemon and 1 Tablespoon dishwashing liquid. Spray away! You'll see results in just a few mins.
Evalyn
Please be careful with salt. It does kill weeds, but it also makes it so nothing else will grow there either. Remember when the Greeks salted the ground on the ruins of Troy so nothing would grow there again? Yeah. (If I've got the Greeks and the Trojans mixed up with someone else, remember I'm a computer major.)
Frankly, it's a waste of dandelions. Who else greets you with a bright sunny yellow face first thing in spring, offering leaves as greens, roots as coffee substitute and the possibility of wine from blossoms then floats away on the breeze like fairies? Try getting that from Kentucky
Blue or Burmuda grass. Dandelions aren't really weeds, they are just plants growing in the wrong place.
Karla
Thanks for the tip. I am putting the kettle on right now.
Krikit
What kinda water would a woman wield if a woman would wield water? Would wielding water waste her weeds wherever and whenever they were? Would a woman wield water to waste her weeds when weeding wasn't working?
OK. I've officially crossed over to the dark side. ~;0)
Susan
You cooked them!