Project: Soil building

To increase soil fertility I thought about various methods and I decided to start with producing Bokashi (fermentation of food waste) in the kitchen. After some research I found that effective microorganisms are necessary to produce Bokashi. I did not want to buy microorganisms as they are an expensive industrial product. So I undertook further research. Inspired by Masanobu Fukuoka (developed natural farming methods) I decided to try to obtain local microorganisms (also called “indigenous microorganisms” (IMO)). Two recipes are included in the Supporting Evidence.

I am still in the process of obtaining but I already achieved satisfying outcomes (see picture on the right).

To document my learning process I decided to use the Kolbs Model. Without a conscious decision I started with Active Experimentation in the Learning Model to then gain Concrete Experience. These are the two quarters where I consider myself relatively strong. In the future I plan to expand my learning style more towards Reflective Observation and Abstract Conceptualization. In the micro-project Indigenous microorganisms I started with my strongest quarters of the Kolbs Model to come closer to my weaker quarters step by step.

• first experience with cultivating indigenous microorganisms, especially in Active Experimentation and Concrete Experience
• gained more theoretical background knowledge

 Principle outcomes summarized

• IMO support independence from industrial products and are optimally adapted to local conditions
  
• read more about usage of IMO
  

 Next steps

• use IMO as ingredient in Bokashi
  
• Research and think: where else can I use IMO?
• deepen knowledge about IMO (usage, cultivation)

 New goals

• produce Bokashi
  

On the sandy permaculture area Terra Preta is used for soil building. Every year several new Terra Preta heaps are being set up. To build the topsoil the finished Terra Preta is spread on the garden beds before the plants are planted. Over several years a relatively fertile topsoil developed, which supplies the plants with nutrients. Additionally the Terra Preta is covered by a thick layer of grass mulch so it does not dry out. In the Supporting Evidence you can find a recipe (in German) how we produce Terra Preta.

My primary achievements

• field of application of Terra Preta in the vegetable growing area
  
• setting up Terra Preta heap
• first attempt to produce charcoal with a special woodgas oven (Chantico Terassenofen)

Principal Outcomes summarized

• very effective soil building method
  
• Terra Preta has a high potential, in a global as well as in a local context

 Next steps

• look for different methods to produce Terra Preta
  
• try to use IMO within a Terra Preta heap

 New goals

• implement one other production method
  
• increase theoretical background knowledge by using ArCEA

I am interested in the local soil composition, so I decided to carry out a sedimentation test. This test provides insights about the different fractions of the soil. I was able to get samples from a depth between five and 30 cm (topsoil) and a depth between 30 - 140 cm (subsoil). I put the samples in jars and mixed them with water. Then I heavily shook every jar. After two days different layers had settled according to the different size of the soil particles: the heavier particles settled on the ground and the lighter ones above.

 The jar with the topsoil (left picture, 4cm high) consists of:

• 1cm humus
• 3cm fine sand

The jar with the subsoil (right picture, 5cm high) consists of:                                                                                                                                                   

• 1cm clay
• 2cm fine sand
• 2cm sand

This test clearly shows how poor the local soil normally is. With its little water retaining capacity it is necessary to build and improve the soil if you want to grow vegetables.