Meeting Dr Reckin & making “Terra Preta” fertile soil

by | Aug 15, 2014

How to make Terra Preta soil, or “From silica alone to 73 elements” with Dr Jürgen Renkin.

For some reason I expect to meet a tall, serious, imposing German man. We open the gate and descend into a verdant, diverse food garden. Jürgen is there by the front door waiting for us, smiling sweetly. He’s shorter than me.

“That was what the soil was like when I moved here six years ago,” Jürgen began, pointing to a small bare and sandy patch of earth not far from the from door.

“There was only one element present – silica. So I had to add the other 72.

“It’s very easy. Anyone could do it.”

He’s a twinkly-eyed, all together charming fellow. To begin to make Terra Preta, one needs biochar. Jürgen has obtained some already, and starts by showing us how to pulverise it.

“If it’s too chunky, it won’t work. It needs to be the right size for the worms.”

Jürgen has designed a simple machine with a spinning blade and small electric motor. To pulverise well, the biochar must be dry, and Jürgen also adds dry wood shavings to aid the process.

Within five minutes we have a ground bucket of biochar/wood shavings.

“Now, come with me.”

Jürgen sets off toward the back of his garden, past a patch of the most beautiful comfrey I’ve ever seen, with flower spikes reaching a metre and half tall. Thriving strawberries spill onto the narrow path and his nursery of densely planted fruiting trees are some of the healthiest I’ve ever seen.

We stop beside a few neat, low, rectangular-shaped compost piles. Pulling aside a bird-net, Jürgen carefully disturbs a clod of earth with his hoe, to reveal black earth and the fattest worms we had ever seen.

The piles, he explains, are a potent mix of chipped and spliced wood innoculated with biochar, microbes, stonemeal, and a special kind of clay found in France. He doesn’t add green waste, believing it unnecessary. That, he says, is used elsewhere (and where, we never did have time to find out. I believe he makes comfrey teas and the like.)

The soil and the plants speak volumes for his method.

Jürgen demonstrates how to prepare woodchips for making Terra Preta using a specialised machine that can both chip and splice.

“The machine is expensive, about 1500 euros. It’s worth it – I couldn’t make soil this quickly without it”.

Jürgen passes a large bucket of woodchips through the machine up to 6 times to ensure they’re cut finely, combining it with the biochar/shaving mix in a wheelbarrow afterward.

Wood is poetry for the soil.

This is an old German saying that Jürgen likes to repeat.

In the context of his black Terra Preta soil and thriving plantlife, it rings powerfully, beautifully true. Jürgen was invited to Australia back in 1994 to visit the progressive Yoeman’s, who’ve published the book, Yoeman’s Keyline Plan. He had it on top of a pile by his bedside table. He also uses the same principles of the Terra Preta Sanitation system put forth by our Berlin friends, Gregor Pieplow and Dennis in their documentary, Undune.

Our special thanks to Julian & Jessica for hosting us Eberswalde, and making this valuable meeting possible.