Definition: Soil organic matter (SOM) refers to the carbon-based materials found in soil that generally come in the form of soil microorganisms and plant residues, detritus, and humus.
Soil Organic Matter in the Forest Garden:
Farmers in the Forest Garden Program discover early that soil organic matter is essential for healthy crop production. During the process of decomposition, microorganisms in the soil break down plant waste and release nutrients like nitrogen, phosphorus and potassium – all crucial elements for soil health.
Benefits of soil organic matter include erosion prevention, improved soil structure, increased fertility, and enhanced water-holding capacity. Soil organic matter also stores a lot of carbon, turning every Forest Garden soil into a carbon sink.
Composting is one of the best ways to integrate organic matter in Forest Gardens. Farmers prepare their compost pits or piles to ensure that the excess organic material they’ve produced can be cycled back into their soil. Learn how to develop your own compost in Chapter 14 of the Technical Manual.
Other methods for using soil organic matter include manure, mulch, wood ash, cover crops, compost tea, and peat moss. Discover when and how to apply some of these soil amendments in Chapter 5 of the Technical Manual.