In an effort to control weeds without the use of herbicides, I recently purchased a propane weed torch. The process began with a little research to see what was available (Google is your friend), and visiting a gardening forum for recommendations as well as basic instruction of use.

There are a few different manufacturers of propane torches, with units ranging in price from $15 or $20 up to $180. On the low end of the scale is a J-hook shaped torch to which disposable bottles are attached.

These are little more than a bent piece of tubing with a large shroud on one end. Some have a piezo igniter, most don’t. Some have a handle, some don’t. The general consensus is that these units are too small to produce sufficient heat and use non-refillable, disposable tanks too quickly, making for inefficient and expensive use.

The next option is a unit with a hose that attaches to a propane cylinder (i.e. BBQ tank). There is little difference between the less expensive units of this style and their higher end counterparts. All of them have a shrouded nozzle, orifice tip, wand, control valve, handle, and hose to connect to a propane cylinder. The price difference is primarily the BTU rating (40,000 to 500,000) and the accessories that come with the unit - which include different sized shrouded nozzles, a “blast handle” (a control valve bypass that increases flame from “idle” to “full-throttle”), and hose length. Additional accessories include 10 pound tanks, tank caddy, and backpack frame.

Before going further, a thought on tools and equipment. In my experience, more expensive, brand name items generally are of higher quality than cheaper, no-name knock-offs that are so prevailant at warehouse DIY centers, discount suppliers, etc. That being said, I was pleasantly surprised at the quality and features of the unit I found locally at Harbor Freight for $30.

Being that a torch deals with flame, hoses, and compressed gas makes for a dangerous implement of destruction. My main concern with an item of this nature is that it be well constructed. This unit - and its slightly less expensive sibling without the blast handle and piezo igniter - seems to be well made, with components that will stand up to the temperatures generated, provide good performance, and offer long life.

As would be expected with any dangerous tool, the list of warnings in the owners manual is extensive, most notable are the cautions of having a fire extinguisher or water hose nearby during the use of the torch. Assembly is quick and easy, which consists of using teflon tape when attaching the hose with the supplied wrenches. Other than attaching the other end of the hose to the propane tank, assembly is complete.

Before igniting the torch all fittings and valves were leak tested with a soapy water solution (any leaks would cause the soap to bubble) as suggested by the instructions. So as not to have to lug the heavy BBQ tank around, I attached it to a hand truck with bungees so that it could be easily and safely transported from one place to another. This is little different than the tank caddies available for purchase. It is important to keep the tank in an upright position while in use or the torch will not function properly. There is a “trick” to lighting the torch, and that is to just barely open the valve to allow minimal gas flow, otherwise the “wind” created by the high flow of gas does not allow the torch to light. Once lit, the control valve is then adjusted so that the flame is solid blue in color and yellow at the tips. This sets the “idle” flame height. Depending on what you’re trying to burn, you may increase the fuel for a hotter flame. This particular unit came equipped with what’s called a blast handle, which overrides the idle flame height and puts the torch at full-throttle. This is handy for economical fuel usage during general weeding, yet with the flick of a lever jump to maximum output to fire off more stubborn vegetation, brush, or stumps.

After initial operation of the torch, a few things stood out that would improve mobility and function. First, for large, heavy propane tanks, the use of a caddy of some sort is a requirement. Next, the 6' length of hose provided is long enough to get caught under the wheels of a caddy, yet too short to reach very far without constantly moving the tank. The fix would be to purchase a longer hose (any major propane supplier can custom make or order one for you), which will allow the tank to stay in a central location while having a convenient and safe working distance. Or, purchase a smaller 10 pound tank and special backpack frame so that you are not tethered to anything.

Now on to what you all want to know - just how well does it work? See for yourself:

Before:

After:

Again, these are tender young weeds so the flame was set at the lowest possible setting. There were a few tree and shrub-like weeds that were more woody and tough and required a slightly longer burn, but only ever-so-slightly. Upon instruction from the gardening forum, the point of flame weeding is not to turn the plant into a pile of ash, as all you’ve accomplished is to remove the visible portion of the weed. The roots are still perfectly safe, happy, and intact underground and will resprout new greenery immediately. What you are trying to do is damage the plant beyond regeneration, which is done by scorching, not burning. The application of extreme heat causes the moisture in the plants cells to boil and rupture, whereby the plant will “bleed” to death, killing roots and all.

Along with the satisfaction of seeing the weeds “going up in smoke”, there is also the audible benefit of hearing them scream. Ok, so it’s not really screaming, it’s more of a pop and crackle, and this is your cue that you’ve burned them long enough, any longer and they will be charred to ashes, which as earlier mentioned, should not be your intent.

It is uncertain as to how long the burned areas will stay weed free. Updates will be added periodically that will monitor progress. For now, the kids are happy for a chemical free environment in which to play:

One final note, the weeded area shown above is near wood fencing and structures. Not only was care used not to ignite these structures, the area was sprinkled with water afterwards to put out any possible smoldering pieces of twig that are embedded in the gravel. A couple of tests were also done in the flowerbeds surrounding the house in which shredded tree limbs are used as ground cover. The torch easily lit the damp twigs on fire as it toasted the weeds, necessitating the use of a hose to put out the flame. As of this writing it is still early spring and things are still pretty damp from recent rains and winter season. The point here is that the intense heat of the torch is something to be reconned with. Even in a low flammable environment the likelihood of starting a fire is extremely high and likely.

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