I felt the answer to this question deserved a blog post of its own, and which can then be referred to in future posts around no-dig approaches to food growing.
How nature replenishes itself
How I understanding permaculture is that it draws on nature as a teacher. Nature can be an example of how to nourish and regenerate the earth.
Nature demonstrates deep and coherent principles of sustainability, and if through witnessing and reflecting on nature, we can be humble enough to allow nature to be our teacher, there are principles we might discover that nature embodies and that we can apply in creating our own systems, whether this be around food growing, economic systems, or social ones. Of course these can all interact, and that is one of the beauties of this interconnected dynamic world we are part of!
So, back to digging. If we look at nature, we can see that it rarely digs in the sense that it rarely dramatically inverts the soil. Instead, nature tends to work gently. In a forest, for instance, leaves fall, they slowly breakdown on the surface, and are gradually taken to deeper layers, in particular through earthworm activity. This process of organic matter being left on the soil surface and taken down (without digging) is a part of the process that naturally builds the fertility of the soil and feeds life, a foundation for the creative effortless development and sustenance of a forest and the abundance that comes from it for an incredibly diverse range of life forms.
Drawing on Nature’s principles
Permaculture would be not about copying this exactly, but about drawing on these principles to design systems (permaculture is a design approach) that provide for our needs in a sustainable way – which means also caring for our wider family: the earth and our fellow human beings.
Choosing to minimise digging
Breaking it down a bit more, here are some specific tangible reasons for not digging (or at least minimising it):
- By inverting the soil, many microorganisms accustomed to living and functioning at a particular soil depth will die, and this impacts negatively on soil fertility (and increases the need for adding fertilisers/external inputs).
- Digging can bring weed seeds to the surface, increasing the need for further digging and leading to an upward spiral of digging! Instead what we have been doing on our plot is, in part, seeing weeds as a form of life that store valuable nutrients. By just hoeing weeds along the surface of the soil, we leave them on the surface (as mulch) where they suppress further weed growth and break down naturally, gradually releasing nourishment for other life, like leaves do when falling on the soil surface in a forest.
- Soil is a carbon sink. Digging releases the carbon stored in the ground into the atmosphere, so is counter to what we ideally want to be doing to reduce greenhouse gas emissions.
A bit of an experiment!
When we began our plot with a no-dig approach, it was a bit of an experiment! We were not sure how things would turn out. Although it’s been only nine months and it’s raised eyebrows, we’ve certainly found that weed growth on our plot seems to be much less now than on many others in the area, meaning less work in the long run, and the soil looks much richer as well.
While digging is something I would try to avoid where possible, there is an unofficial permaculture principle that underlies all of them, and prevents permaculture from becoming dogmatic. This principle is ‘It depends‘! After all, there are instances where some kind of digging would be appropriate and helpful (e.g. in heavily compacted soil). The aim, instead of no digging [full stop], is rather to create the conditions that minimise the need to dig, particularly over the longer term, and that means digging as little as possible in the first place. In our case, we have been fortunate whereby we have got away essentially without digging the soil at all.
All the best to everyone who is working (or working less!) to do this, and thank you to all my teachers who have helped me to explore the wonderful approach of permaculture which continues to support me in drawing on principles in nature to inspire my work in all its forms.
I have found these two books to be really helpful (and both of which have pages about tilling/not tilling the soil):
The Permaculture Garden: by Graham Bell (simpler)
The Earth Care Manual: By Patrick Whitefield (more comprehensive)
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