No-dig Growing and Compost making

I am lucky enough to have an allotment, though it’s a small one. The traditional size for an allotment is 10 rods, poles or perches – which means 250 square metres. But like most people on the Town Council’s allotment site in Glastonbury I have barely a quarter of that; and by the time I’ve found space for a shed, three compost bins (I shall get on to why three later), an apple tree, and pathways so that I can get to all these important things, the space left for actually growing veg is less than half the total area. It makes a significant contribution to my diet for a few months towards the end of the summer and into the autumn – but I am a very long way from being self-sufficient in food. In such a small space, an allotment can be no more than a hobby.

However, it can also be a place to experiment. I have recently got interested in ‘no-dig’ growing, which is attractive because digging is such hard work; and lately it’s been popularised locally by the example of Charles Dowding and his no-dig salad crops. But he, it turns out, uses extensive quantities of compost, which can be equally hard work to make as is digging. And anyway, why? I thoroughly agree with the idea of organic growing, so I continued to make modest quantities of compost and used it to refresh the soil by digging it in; but it was only when I started getting interested in regenerative growing – reading and watching videos – that I understood more. That’s when I began to experiment.

Year two: an encouraging start for my no-dig experiment.

Year three: looks impressive at first, and I’m hoping for a good yield … but all that soil brought a lot of weed seeds with it.

The soil on my allotment is solid clay. It used to have a bit of genuine topsoil, but a former tenant had apparently stripped it all off and dumped it in the hedge, which seems to have been his method of weeding. When I took on the allotment it was covered in long grass, and I only heard about this later. The first year I dug the plot and planted potatoes, hoping for the best: most of them got eaten by wireworm. I dug it over again, adding the contents of my compost heap and a dozen bags of agricultural grits (very course sand, which is meant to make clay more workable). It all just disappeared.

The next year I had become more systematic with my compost making, collecting barrowloads of nettles and comfrey leaves from around the margins of the allotment field. This was piled up, layer upon layer, in the first compost bin. Half way through the summer it was full, and I turned it over into the second bin; at the end of the summer the second bin had rotted down well, and I had room to do this a second time. Meanwhile, at home, I had also built myself a new garden shed, which involved leveling the ground. It produced a dozen or two bags of rich loamy soil, which helped. That year the results of my new no-dig experiment were an encouraging start, and even impressed the old Somerset gardener who had an allotment just down the way.

By the third year I’d had a new set of garden steps built at home, and that produced nearly a hundred bags of the same rich soil, which means that I could successfully replace what had gone missing. I spread as much compost as I could make over the growing beds, and a somewhat deeper layer of the soil on top of that. The result looks impressive, and so far seems like it will support an improved yield – but next year I shall have to rely on just my own compost. Also, although I clearly remember my late friend Patrick Whitefield (the permaculture teacher) saying that a compost heap needs both ‘greens’ and ‘browns’, mine has so far consisted of nearly entirely greens.

If you have no easy access to manure, nor any straw that’s been used as animal bedding, then the two materials most likely to be available for composting are grass mowings and leaves – though the first thing you will notice is that they are not both available in quantity at the same time of year. I had always avoided large quantities of leaves, telling myself and anyone who might want to listen that leaves have a different method of decomposition than grass and soft green leafy plants, and was best used separately. I worked as a gardener for a few years in my twenties, under the mentorship of ‘old Harold’. Each autumn we would go into the woods with the tractor and trailer and collect as many bags of leaves as we could carry, then tip them into a chicken-wire container to make leaf mold. Harold told me that a fungal mycelium grew within it, breaking down the leaves; you could smell the difference between leaf mold and an ordinary compost heap. We used it, when it was ready, mixed with sand and sieved soil to make our own potting compost.

When I started reading about regenerative growing I discovered that the ‘greens’ encourage bacterial decomposition and the ‘browns’ fungal. By ‘fungi’ I mean not mushrooms and toadstools but microscopic fungal cells that grow through the soil in long threadlike structures or ‘hyphae’, that form a mass known as a mycelium. They perform important functions within the soil including nutrient cycling, disease suppression and water dynamics, all of which help plants become healthy and vigorous. Digging and ploughing, along with fungicides and other chemicals spread on modern fields and gardens, disrupt and destroy the mycelia – most importantly that of mycorrhizal fungi, which attach themselves to the plants’ root tips and effectively increase the reach of the root system considerably. The fungi deliver nutrients and moisture direct to the plants – whilst receiving sugars, formed by plants through photosynthesis.

Both fungi and bacteria are important decomposers of organic matter, and thereby release nutrients into the soil, though the relative proportions of bacteria and fungi is an important factor. Annual plants, including most vegetables, obtain their nutrition mainly from material broken down by bacterial activity, whilst trees and bushes – i.e. fruit, if we’re talking food growing – obtain theirs mostly from tougher material broken down by fungal activity. Healthy soil needs both, but in different proportions depending on what you want to grow.

You can refine this basic idea and get as scientific as you like – buy a microscope and identify the microbic life in your soil. You could then design compost to correct soil imbalances and to support the particular fruit and vegetables that you wish to grow. For now, I am happy with approximations and to see how it goes – depending on what is available for composting. I have just about got space to make a third compost bin on my allotment. Come the autumn, I shall fill it full of leaves – in honour of Harold –  so that by the spring I shall have plenty of leaf mold to mix in with my next batch of compost. For now, I continue to watch and learn. I have planted some first early potatoes, which I discovered last year are not affected by worm as long as you dig them up nice and early. They are already coming up, and looking happy.

* I’d just posted this article when I bumped into Ark, the recently retired gardener at the Chalice Well Gardens. He pointed out that when leaves turn brown and drop off the trees, the nutrients that they included have already been absorbed back into the tree. Leaf mold is therefore not something that feeds the soil, like compost; it is rather a soil conditioner. He also told me that if you spread compost on the ground and sow seeds straight into it, the result is likely to be detrimental with the plants becoming ‘leggy’ with excessive nutrition when they are seedlings. So I have decided to continue with my intention of mixing leaf-mold and compost, hopefully giving me both more bulk to cover the ground and supress weeds, and less concentrated nutrition – all part of the experiment!

Ark expands on the subject of compost making in his book ‘The Art of Mindful Gardening’, by Ark Redwood, published by Leaping Hare Press, 2011, see pages 29-36.
See also ‘Teaming with Microbes’ by Jeff Lowenfels and Wayne Lewis (revised edition), published by Timber Press, 2010, see pages 131-138. Focussed more on encouraging bacteria and fungi, and the balance between the two, it recommends incorporating autumn leaves directly into the compost heap.