Instructions for Use – Description

Using Your Best BioChar Kiln


First, place the Best BioChar Garden Kiln in a level place where there are no nearby flammable materials, small children and pets as there is a flame and the metal will get hot. Have a hose or bucket of water handy for safety and for dousing the biochar when it is done.


The metal of the kiln gets HOT! Also, the metal is relatively thin (.032″) so protect your hands. The chain handles are quite useful. If you need to move the kiln while it’s still hot, put a strong metal rod through the handles and do a two-person carry – carefully!

Best BioChar Kiln Starting


Seal air leaks, Start the fire

First, put a little dirt in the bottom of the cone around the edges to seal air leaks, or push dirt or sand up around the bottom seam. Build a small fire in the bottom of the kiln and keep adding fuel. as the white ash just begins to form. The materials should be of fairly uniform size. Keep adding, building up the depth of the biomass, but avoid extinguishing the flames.

Your fuel does not have to be as uniform as the photo, any materials up to 2″-3″ will work. Place the larger materials in the middle of the kiln for best results.

Best BioChar Kiln Add Sticks
Best BioChar Kiln Progress
Best BioChar Kiln Let it Burn
Best BioChar Kiln Gasses
Best BioChar Kiln Slowing Down
Best BioChar Kiln Almost Done

Keep adding more

The idea is to pile it up as fast as possible without smothering the fire.

Once you get the hang of it and recognize the progression from fuel to char to ash and when to quench, you can fill the cone kiln with your dry fuel and simply top-light the pile. You can add more material once the flames are well-established.

Regardless of the technique you use, the priority is to avoid making smoke!

Fill it to the top

Stop adding more when it’s about level with the top.

Let it burn!

Middle of the burn

Notice how the flame on top heats the fuel underneath it, causing flammable gasses to be released and drawn in the flames instead of going into the air as smoke, particulates and greenhouse gases. You can see the gasses igniting around the edges of the kiln. This is what makes the kiln work and stay smoke-free: the rising gasses ignite and shield the material beneath from oxygen. This creates the “pyrolysis zone”, cooking the material below into charcoal.

Slowin’ down …

At this point the material will begin to settle and you can add more or just finish this batch. The volume will reduce by about half because some of it is vaporizing into flammable gasses.

Almost done!

Best BioChar Kiln Done


Best BioChar Kiln Quench

Quench it!

Give it a good dousing, stirring it with a shovel or stout stick – there’s a lot of heat in there. We don’t want it to re-ignite when we’re not looking or continue to smolder and create more ash than biochar. The biochar is made, let’s use it!

Best BioChar Kiln Car Smashing

Smash it!

Break the biochar into rice size pieces. Drive over it with a car or smash it with a board or what have you. If you’re ready to take it to the next level, purchase a leaf blower (with a catch bag and metal impellor), reverse the air flow so it becomes a vacuum. Suck up your cold, slightly damp biochar directly out of the kiln. The bag will fill with lovely uniform pieces of biochar about 1/2″ or so in diameter.

As always, when handling biochar, wear a mask!

Best BioChar Kiln Smashed Char

Now that it’s smashed …

Mix it with compost (aim for ~10% biochar in your pile), worm tea or manure to inoculate it with soil microbes. Then spread it out on the soil. The most you’ll need to add at once is 10% by volume (1/2″ layer, worked in 5″ deep). But any amount helps! It’s simple to build it up over time and a bit easier for the soil life to adjust to this new element.

If you have larger chunks, just use them as mulch or top-dressing. They’ll work into the soil on their own. If you have issues with leaf-eating worms, sprinkle the biochar thickly around the base of plants and leave it on the surface. Biochar’s micro-sharp surfaces work better than diatomaceous earth; worms do not want to crawl over it.