At the end of last year, I had an interesting conversation with Alan Marshall at Roedale Valley allotments all about ‘exudates’. “What’s that?” I asked and the resulting conversation led to Alan writing this article about no-dig gardening and soil biology.
I’ve read and tried most of the theories and principles of no dig, mostly permaculture, which was designed for the tropics, so in our temperate zone there is not a lot you need to take from it, just the basics: no bare ground, always have plants growing, mulch where there are no plants and ‘chop and drop’ vegetation onto the soil surface.
Once the soil is good, it retains moisture [Ed-for more info on what makes good soil, see Ruth’s Urban Gardening Course]. I have not watered for a least 20 years and that’s down to the soil biology. You are probably aware that plants take in carbon but plants have what are called exudates in their roots and these give out carbon which attracts and feeds the bacteria, microbes and fungi, in exchange for all the elements and nutrients the plants require. Research has shown that one microorganism, arbuscular mycorrhizal fungi, produces glomalin, a protein that binds soil particles and stores both carbon and nitrogen. It also stores water, gives soils their physical condition the crumb effect that sticks together and stops soils drying out.
Sadly, I don’t think I have ever convinced anyone to do no-dig which is a shame because the way people feel about the climate and ecology, no-dig ticks most of the boxes. By not tilling you do not release carbon and by keeping plants in the ground and having as many perennial plants as possible you will sequester carbon and feed the soil life.
This article is just a taster since the topic is quite extensive and I have dealt with only one aspect of it; there is a lot more to learn. If I have aroused anybody’s interest they need to look on the internet for no-dig gardeners & farmers: Charles Dowding and Richard Perkins, scientists Dr. Elaine Ingham and Dr Walter Jehne and anything to do with regenerative agriculture. Once you start looking you will find others. Enjoy the search!