DIY ELECTRIC WEED BURNER (WHEELED)

Here is a quick Heath-Robinson weed-burner I made using a cheap heat gun I already owned, and old stabilisers rescued from a kids bike. It has proved great for burning off small weeds in paving, gravel and brick path joints.

Commercial electric weed burners are pretty cheap, but usually don’t have wheels, so can put strain on your back when holding them out in front of you. My rough-and-ready DIY version has excellent handling, no back strain at all. It is easy to manoeuvre except in very narrow spaces. By raising and lowering the handle slightly, the tip of the heat gun can be brought closer or further from the target. Another benefit over the commercial variety is that I can remove the heat gun in seconds and use it as originally intended e.g., paint stripping.

Such weed burners are particularly effective on small weeds, especially where they are in gravel or paving, as hand weeding in these situations can be difficult.

Although they are called ‘burners’ it isn’t necessary to actually incinerate the weed to kill it. Enough heat to make the plant wilt will kill annuals, although perennials need heat concentrated on their centre for up to 8 seconds to kill the growing point and prevent regrowth. Established, deep-rooted perennials (like dandelions), are unlikely to be killed, and will probably regrow.

I have a feeling that regular use of my weed burner will sterilise the soil around the weeds, hopefully killing some dormant weed seeds too.

Why not use weedkillers?

Weedkillers can be faster (to apply) and more effective on large areas of established weeds where an electric weed burner would struggle. However, on patios and block or brick paths, much of the weedkiller ends up on the surface of the paving, which is wasteful. For the areas of paving and paths in my garden I use a 7L pump sprayer, which is heavy to carry around. Also, the spray lance is only 60cm long, which requires me to bend to target weeds at ground level, leading to back and shoulder strain. The nozzle needs regular cleaning otherwise it starts to drip. Even a small amount of wind can cause weedkiller to drift onto adjacent plants. Add to this the fact that weedkillers are becoming increasingly expensive. No wonder many of us are looking for alternatives.

I will use weedkiller when I have to, but by using my DIY weed burner regularly, I hope to reduce my dependency.

electric vs gas

Weed burners come in propane gas and electric varieties. I’ve tried the propane ones before, but the screw-in canister type only last for one hour and cost about £8 per can of gas. There are varieties that run off large (BBQ size) gas cylinders, but these need a trolley to move around the garden and take up much more space to store. Electric versions are much more compact and economic to run, using only £0.50 of electricity per hour to run. However, they require an extension lead, making them less suitable for large gardens.

Benefits of Electric Weed Burners

Demo Video

Note: the noise is minor – considerably less than a lawnmower, hedge cutter or strimmer.

How I made my electric weed burner

I repurposed an existing heat gun I already owned. Heat guns are simple devices – like super-hot hair-dryers — used for DIY projects such as paint stripping. Mine was rated at 1.5kW, and works well enough for my use. 2kW versions are available which might be even better. They can be purchased online from as little as £13.

Most heat guns come with a variety of adapters to direct the heat. I found the narrowing circular adapter best as it focuses the heat on one spot about 1 in (2.5 cm) across.

The aim of this DIY project is to fit the heat gun to a handle and wheels to make it easy to push around in the garden. Take care when planning to ensure the heat gun nozzle sits at the right height above the ground when being used:

1. HANDLE

For the handle, I used a 1in x 1in treated timber (an old tree stake). I cut it to length to make a handle so I could use the heat gun without bending. I attached two kid’s bicycle stabilisers to the handle to give it wheels – this significantly reduces shoulder stress compared to commercial lance-type weed burners. If you don’t have stabilisers, any wheel (even a single one) would be better than none.

2. WHEELS

Adding wheels was a brainwave that made this project so successful. I used a pair of child bicycle stabilisers that I had lying around, which by luck could be fitted to the handle securely with just a single through-bolt. However, I am sure any small wheels would be better than none, but the brackets on the stabilisers worked particularly well, giving me a width of about 10 inches (25 cm). This made the weeder incredibly stable in use, with the only downside being that the weeder doesn’t fit into tight spaces.

3. FRONT CLIP

I wanted a simple ring/loop that the heat gun could slot into, which would hold it in the right position above the ground. My heat gun has a tapering plastic neck, so I thought it might fit snuggly into a suitable diameter loop.

For this I used a suitable sized jubilee clip, which I screwed to the upper surface of the handle, near the wheels. This involved drilling a 2mm hole through the clip to take a small screw. The jubilee clip only needed an initial adjustment to get the right diameter, so that the heat gun could be slotted in and out, but I did not tighten in onto the gun barrel as it wedged in sufficiently tightly when pushed in, leaving it easy to pull out at any time (e.g. if I need to use the gun for paint stripping).

4. REAR TIES

The rear tie keeps the gun parallel with the handle, and prevents it falling out of its lower jubilee-clip holster. I used galvanised wire to hold the rear of the heat gun in place. Wrapped around the handle a few times, then twisted tight across the back of the heat gun. It turned out to be surprisingly stable. And with a few counter twists the gun can be removed. A rubber band might have worked equally well.

5. CABLE TIES

Finally, I tied the cable along the handle to keep it out of the way and stop it pulling on the heat gun when in use. I used string, but mini cable ties would be ideal.

So there we have it: my favourite new weeding tool!