While many home gardeners whip out the trowel or the sprayer to deal with weeds, there’s an easy, chemical-free option that most gardeners haven’t yet tried. Weed torches are a great no-bend solution for weeds in sidewalk cracks, gravel driveways, or along fence lines where it can be difficult to weed.
Weed torches work by burning off the protective coating on leaves so the weed can no longer hold moisture or photosynthesize. Weeds start to shrivel within hours, and your kids and pets are safe to come out as soon as you turn off the flame. While mature weeds can come back from the roots, 2-3 treatments will knock them down for good.
While the idea of cranking up a torch to deal with garden weeds may seem intimidating, in fact the tool is straightforward to use. You simply light it with a spark (there’s a special tool for it so you can keep your hands safe!), then pass the flame over the weeds a few times. You’ll know you’ve been effective if you can pinch the flamed weed and leave a fingerprint (see below).
You can use the torch within two feet of mature shrubs and trees, but should avoid coming close to herbaceous perennials. It’s also not safe to flame in areas where there’s dry brush or dry conifer needles nearby, and you should avoid torching weed mat. While I’ve never set anything thoroughly on fire while flaming, it’s a good idea to keep a hose at the ready just in case.
For those with cold winters, weed torches are a great multi-purpose tool. A quick once-over with the weed torch can de-ice pathways and make them safe to walk. Thick sheets of ice can be melted at one edge, then lifted and removed from the walkway. You can also use them to sterilize animal cages or thaw frozen pipes.
Two types of torch
I tested two types of weed torch – the Mini Weed Dragon 25,000 BTU torch (handheld, works with a one pound propane tank as shown) and the regular Red Dragon 400,000 BTU propane torch (where you pull a wheeled dolly with a 20 pound propane tank behind you).
(Note: There is also a 100,000 BTU Weed Dragon torch that uses less propane than the 400,000 BTU model, but is otherwise identical. However, since the 400,000 BTU model lets you adjust the amount of propane with a little knob, I don’t see why you’d purchase the model that only has the option for 1/4 the power. You can always turn the propane down on the more powerful model, and the prices are similar.)
The Mini (left) has the advantage of being lightweight and extremely maneuverable. When used with a one pound propane canister, the Mini weighs in at less than four pounds, and since that small canister screws right into the torch itself, you don’t need to stay on stable ground as you do when wheeling a propane tank behind you.
But the disadvantage is that the mini has a much smaller flame and so takes longer to use, and also sputters out on windy days. It also doesn’t have a squeeze valve, so you can’t turn it on and off quickly while operating. I’d recommend the Mini in situations where you will be hitting only small areas of weeds such as in sidewalk or pathway cracks.
If you have a large gravel driveway or just a large property in general, the regular Red Dragon torch with the squeezable on-off valve on the handle will be the one for you, but since that one operates with a 20 pound propane canister you will also need to pick up the wheeled dolly to make it easy to maneuver. The regular is much more powerful and doesn’t sputter out on windy days like the Mini.
Since a pound of propane can last for up to an hour of torching, weed torches are much more economical than organic weed sprays, which work via a similar action (burning off the waxy cuticle on leaves so the plant can’t retain moisture or nutrients).
A great tool, but let’s keep it real
While flaming is an easy (and fun) technique for getting rid of weeds on patios, pathways, and around mature trees and shrubs, you’ll want to keep a realistic idea of what it can do for you. It has very similar limitations to organic weed sprays, in that it is most effective on tiny weeds, and may not fully kill a big, tough weed on the first treatment. It is also most effective when the plant is actively growing, so while you can torch in winter, it works much better in the dry season.
The one distinction I’d make between the action of the torch and organic weed sprays is that the torch, especially the Mini, takes more time to use than just doing a quick spray. Tiny weeds may need two passes with the torch, while tough weeds may need five or more passes with the flame. However, the benefit to torching is that it is much safer in the sense that all organic sprays are incredibly corrosive on skin and in eyes. It’s also a lot cheaper, as a one pound propane canister is $3, and enough spray to do a similar area can run $20+.
One tip for getting the most out of your torch is to plan to do two runs a few days apart. One run to lightly torch each weed just enough so that it shrivels after a couple days, and a second run to actually burn off the dried foliage after the weeds die. This makes torching much neater than spraying because you don’t have to look at the dead weeds sitting there afterwards.
I love my weed torch and use it often on the weeds in the cracks of my sidewalk and along a chain link fence where I can’t easily weed by hand. While you’ll still need to fine-tune within garden beds and around young plants, using a weeding torch is fun, safe, and takes very little setup.
Buy the Mini Weed Dragon here (shown in photos): Amazon.com
Buy the Regular Red Dragon propane torch (with squeeze valve) here: Amazon.com
Buy the propane tank dolly here: Amazon.com
(A much shorter version of this review originally appeared in Fine Gardening Magazine.)