Got stubborn weeds between the bricks in your driveway or patio? I decided to try my home steam cleaning machine on the weeds to see if it could actually kill them at the roots. It’s a good option for anyone who gardens organically and wants an alternate way to stop the weeds without using herbicides or endless hand-weeding.
More tips on weed removal can also be found here: How to Remove Weeds from a Brick Pathway Without Herbicides.

Using Steam to Kill Weeds

No, not a brick driveway again! Please, no!

Brick driveways are not that common around here yet every house we lived in has one. Oy! It doesn’t matter if they look good or not, unless those cracks are sealed, they are relentless weed magnets.
The truth is, brick driveways actually pay weeds to germinate deep in their crevices where no one can reach them. Brick patios hold secret parties where they smuggle in the most invasive weeds to raise entire families below their plain, brick facades. Brick pathways tell us they are such a good, functional solution, all while harboring a multitude of weedy secrets, just waiting to take over, right under our flip-flopped feet.
Watch Video | Steaming Away Weeds
And, lucky me: I have been dealing with these evil-doers for decades.
If you’ve been here before, you know I’m all-organic all the time, and I try to do as little harm as possible when dealing with garden problems. This means, no herbicides or acids like vinegar on the driveway or anywhere else.
And yes, that does mean I have spent far too much time pulling weeds by hand. I don’t mind it in the garden but it’s a whole other level of annoying on the brick driveway.
The gaps between the bricks are so tight that only with great patience and care can I actually wiggle a weed just right to actually remove it in its entirety. And this has to take place after a good rain when the soil has already loosened them (see more smart tips on weeding here), otherwise, it’s impossible. The whole thing is a fine, masochistic game I rarely win. Life is too short for this stuff.

And Then the Genius Got a Better Idea
Just recently it dawned on me that, just as you can use boiling water to kill a plant (if the heat penetrates the entire root system), which can be effective but labor-intensive, I should try using our home steam cleaning machine and see if it might kill the weeds. Same effect, much less effort!
Right?
I’m a genius! Or, I thought I was until I googled it and learned that weed steamers are already a thing and my brilliant idea was about 20 years late to the party. Sheesh!
I have no idea if a household one is truly different than one made for the outdoors, so use the indoor one at your own risk.
Or, you can rent or buy a proper one made for this:
If there’s a chance I don’t have to crawl around pulling weeds anymore, count me in.
And, since steam is steam, I figured the odds were good it would work.
Related: How a Canadian farmer plans to kill weeds by blowing off a little steam (CBC news)
Home Steam Cleaning Machine

We got this McCulloch Steam Cleaner a few years ago when I needed to do some deep cleaning. It works quite well for a variety of hard-to-clean areas in bathrooms and kitchens, especially when the only alternative is cleaning products that pose too much of a hazard to humans.
Watch Me Steam Weeds
It’s more exciting than paint drying, I promise! And the drama—wow!
Click the play button to watch:
McCulloch Steam Cleaner | Amazon
My steam cleaner holds four cups of water. It heats up in about 10 minutes and provides about 30 minutes of steaming.
It comes with various attachments, much like a vacuum cleaner does, making it easy to direct the steam as needed.
For cleaning, the steam basically loosens whatever dirt or grime is present, and you can immediate wipe it away with a rag. I like that you don’t have to wait and see if it’s working: results are instant, and you can repeat the steam right away as needed.
For steaming the weeds on the driveway, I attached a triangular brush to smother those terrible beasts, one at a time.
Related: 7 Essential Weeding Tips Every Gardener Should Know
1Day One

Here’s how the driveway looked at the beginning.

Why is my driveway such a hideous, weedy mess, you ask? It’s all in the name of science. I intentionally let the weeds grow extra long so I could really put the steam machine to the test. Or, that’s my story and I’m sticking with it.
Using the Steam Cleaner on Weeds
I set the machine to constant steam and aimed the brush at each weed for 4 to 8 seconds. Sometimes I realized I was being too quick, so I would go back and give them a double dose.

If it’s a choice between pulling out weeds on my hands and knees, or standing and aiming steam at them, my vote is for steam every time.
Three Hours Later
I could see changes in the weeds almost immediately. They had started out green and happy, and, by three hours later, they were looking a little beat up.

There was still lots of green, but they were slumping over and looking parched. I became cautiously optimistic. But I have been fooled before. Obs!
2Day Two
It rained heavily after Day One and I thought that might perk the weeds up. But no! They continued to look dry and unhappy—a good sign that the steam had worked, although I was still skeptical whether the roots would truly be killed off. Never give weeds the benefit of the doubt. They know when we are feeling weak and forgiving…

3Day Three
Things appeared drier yet on Day Three. I also noticed where I had missed some weeds.

4Day Four
By Day Four, I could tell the party was over for the weeds. I pulled a few of them, and their dried-out roots came right out of the cracks. Is this what winning feels like? For reals?

Instead of waiting, I decided to steam any weeds I had missed the first time and reapply it to any that still had some remaining green growth. You must go in and finish the job while the enemy is weak, said somebody.

5Day Five
We’re calling this one early! I thought it might take weeks, but, by Day Five, I could see that the weeds were truly dead or dying.

The steam cleaner was a weed-killing success. Had my brilliant idea taken place decades earlier, I would now be receiving accolades from around the globe. Oh, to travel back in time!
The Next Step

But, before we dance off into the sunset, we must be realistic. Brick weeds never give up that easy. They are here to taunt us, any way they can.
So long as you have bare soil, more weed seeds will eventually germinate in the cracks.
My next step is to remove any soil from between the bricks, probably with a power washer.
After that, I will fill the cracks with polymeric jointing sand. This is a product that, when damp, expands to fill gaps and solidifies.
I had applied some a few years ago, but I did not apply it everywhere, and the weeds battled here were nature’s sweet reminder of that.
We must remain vigilant!
And cheers for this small victory.
The steam cleaner worked: it definitely killed the weeds at the roots. Some needed a second application where I missed giving them a good dose the first time, but in the end, everything withered and died.
I did not have any more weeds for the remainder of the season.
I also liked finding another use for the steamer, which we otherwise rarely use, and, better still, I did not have to crawl around in the blazing sun trying to pry the little beasts out of the gaps.
Not that I’m bitter or anything. Darn you, brick driveways!
~Melissa the Empress of Dirt ♛