How do I make Amazonian Dark Earth (aka Terra Preta) in the HOTBIN Mega?

Amazonian Dark Earths (ADE) are thousands of years old and the recipe is long gone. We do not live in the Amazon Rain Forest, nor are UK soils and conditions the same as those in the Amazon. In truth, what we are suggesting is making the closest thing in terms of fertility and soil performance to the ADEs:  A modern-day Terra Preta sometimes called Terra Preta Nova (TPN). 

We think our method and the final product is world-leading. 

Why not have a go and make your own biochar super compost?  Add it to your soil and create the nearest thing to ADE/Terra Preta.  

Making Terra Preta in the HOTBIN Mega is easy!

• Start your HOTBIN Mega as usual by filling it with compostable waste 
• Sprinkle on the Biochar Compost Activator / Humification agent (about 10% by volume)
• Let it compost down

How to use the HOTBIN Biochar Super Compost to make ADE 

What you get out of HOTBIN Mega when using the Compost activator is  “biochar super compost”. Mix this biochar super compost  with your topsoil:

• 1 part biochar super compost, 3 parts loamy topsoil 
• 1 part biochar super compost, 1 part clayey or sandy topsoil

(Topsoil varies a lot – if you have reasonable soil then use a 1:3 ratio if you have poor soil, use a 1:1 mix)

Is making ADE really that simple?

Yes. All the hard graft and science is behind the scenes. If you want to know more see below, otherwise have a go.

Why does the SoilFixer ADE recipe work?

If you want to know why the recipe works, the overview is as follows

• The compost conditions inside the HOTBIN make more colloidal humus than traditional composting. (The exact conditions we use are patent protected – it’s just a happy coincidence that HOTBIN supports most of them)
• The addition of biochar and trace minerals (i.e. the compost humification agent) makes even more colloidal humus
• Colloidal humus (link) and biochar work together to give huge increases in plant growth 
• The biochar super compost made in a compost pile gives better plant growth over adding biochar directly to the soil, and better growth over compost mixed with biochar and then added to the soil.  

It is our hypothesis that our ancestors never deliberately added biochar (wood charcoal) to their soil to increase soil fertility. We believe they put many “waste” materials such as food residues, fire pit ash and faeces into middens (toilet pits). Such pits acted as compost bins. After a time, they noticed more vigorous plant growth around such covered pits. They found that adding the contents of the old pits (“biochar super compost”) to their fields increased crop growth. At SoilFixer, we have used our composting knowledge to work out which things need to be added to the compost waste and which composting conditions were likely to be present in the midden pits.  We then set about replicating them and finding compost systems that supported the recipe and method.   

Can I use plain, raw, virgin biochar instead of your Compost agent in the HOTBIN Mega?

Yes and it will work to a degree.  But rest assured, we first tested adding just biochar into the compost heap. What made the step change difference was biochar plus the trace minerals.

What is SoilFixer Compost Activator (Humification Agent) made from?

Our agent is 80% biochar, 15% trace minerals and 5% compost.