Terra Preta

How to make a "Little School Garden with Terra Preta"

By Ulla Ondratschek , Primary school "Grundschule im Beerwinkel" / Berlin


A composter made from wood (prefabricated or home built , (about 1 m X1 m)

 For building up:

  • Green waste, shredded twigs, leaves etc, lawn clippings, food left overs (cooked or uncooked), organic waste, coffee and/or tea grounds, soil, garden earth
  • Terra Preta Mixture: stonedust and charcoal 2: 5 (you can buy it at Tria Terra
  • EM Bacterias - also gained from  Yogurt or soured milk
  • Watering can and water
  • Gardentools: shovels, secateurs, shredder (if necassary)
  • Earthworms will come on their own. If you have no earth worms you could ask at a farm to find some in the compost.

How to make it:

  • Build up the composter or make  a high bed on open ground (not sealed earth!)
  • 1st layer: rough cuttings of twigs

then in layers:

  • soil and compost, organic waste, food left overs,
  • Terra Preta mixture with EM Bacterias in  water  ( about 20ml to 10l water) ,
  • water the bed in between each layer with the EMwater,
  • last layer : garden soil

What to plant:

high nutrient  demanding plants like tomatoes, pumpkins, courgettes, aubergine…

in autumn you can sow /plant lettuces and herbs

Ideas to use the garden for teaching:

  • Look at life cycles: plants, earthworms and creepy crawlies, weather, climate, food, garden, ..
  • Look at snails and slugs - life, uses and dangers
  • Discover the content of soil: colour, consistence,smell -   differences to ground or earth, pH value, taking samples of different soils….
  • Grow your own plants
  • Harvesting and cooking
  • How to keep it fresh?
  • Building up an expert team on Terra Preta, sharing the knowledge with  the other students

For making your own pyrolisis oven for charcoal : Ayumi Matsuzaka  http://www.oberwelt.de/projects/2012/AyumiInitial.htm

For more information about Terra Preta: http://en.wikipedia.org/wiki/Terra_preta