THE NO DIG GARDEN – GROWING VEG THE NATURAL WAY

I recently attended a lecture on the ‘no dig’ system of gardening. Held in a modest village
hall in Devon the room was packed with gardeners and allotment-holders eager to
revolutionise their approach to gardening. Through a side door, a tantalising glimpse of
home-made cakes and pots of tea might have tempted the bored or hungry. However, our
speaker, Charles Dowding, was no mere theorist, but Britain’s foremost proponent and
practitioner of the no-dig method.

With his angular, tree-like frame poised upon the stage beside a giant screen, he
orchestrated his slideshow to an illuminating commentary, the fruit of over 35 years of
experience in productive market gardening. He is clearly both artist and scientist. As an
artist, he works with the medium of soil and seasons to create a changing mosaic of edible
abundance and colour. As a scientist he has developed repeatable methods of production
employing nature’s deepest principles of economy.

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Time ran on and as the talk came to an end our questions, sprouting like weed shoots in
Spring, had to be cut short. People congregated to the front around the speaker and the
table of his books. Behind, a line of plump overwintered vegetables,squashes, parsnips,
beetroots, perching along the edge of the stage silently proclaiming the success of the
system – colourful talismans of reassurance. The tearoom beckoned.

‘No dig’ means just that; no rotovation and no slicing through the soil with spade or fork and
no strenuous turning and breaking of heavy clods to prepare the ground for sowing.
No chemicals are used here either because the system uses natural methods of both
fertilisation, and weed or pest control. The no dig approach is essentially in accord with the
broad principles of ‘Permaculture’ – a sustainable approach to growing that uses very few
external inputs.

The fundamental premise of the no dig system is that the soil is a living, intelligent universe
in itself, designed by nature to support plant growth when cared for properly and left
undisturbed by digging or ploughing. The advantages of no dig are:
Less work for more production and satisfaction: Less interference with, and more
participation in nature’s own methods.

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Fertilisation from the top down: Two inches of compost mulch applied annually on top of
the soil (where it would naturally be found in nature) puts back the nutrients that the crops
take out.

Using nature’s workforce: Worms, which thrive abundantly in the no dig environment, do
the work of carrying nutrients from the surface deep into the soil, creating air passages in the
soil as they do so.

Using the intelligence of the soil: The ‘soil food web’ comprised of fungal threads,
beneficial soil bacteria, other micro-organisms, and creatures higher up the food chain
including worms, remains undisturbed, maximising its capacity to convert and transport
nutrients within the soil. This retains the integrity of the soil structure and regulates soil
moisture content. The need for watering is greatly reduced.

Fewer weeds: Weed seeds are not brought up to the surface by digging. A compost mulch
on the soil surface further discourages weed growth.

Earlier crops: Surface mulches and undisturbed soil structure help to retain warmth in the
soil during the winter months encouraging plant growth earlier in the year.

Continuous sowing/planting: As soon as one crop is removed another can be sown or
planted in the same bed without soil preparation other than clearing the surface debris of the
previous crop. In many cases the roots can be left in the soil. As they decompose, they open
channels in the soil for new plant roots to colonise. Two crops a year are often possible. Also
crops can be inter-planted so that as one comes to an end, another is growing alongside it.
This strategy also out-competes weeds because the soil is always supporting a crop.

Establishing the no-dig garden:
Using his own experience as an example, our speaker outlined the practical steps for
establishing the no dig garden. In November 2012 he started his present and fourth market
garden. At that time it was an overgrown field with the remains of concrete slabs and sheds
which 50 years before had been a nursery. Before being able to generate home-made
compost, he imported a few tons of council-made compost from recycled green waste.
Having dug out the woody weeds such as brambles, he used cardboard covered with
wood-chip as a mulch to kill weeds on the pathways between beds. The beds themselves
followed two patterns: One was simply to cover the grass with 6 inches of compost and plant
straight into it. The other was to put 2-4 inches of compost straight onto the grass covered
with a further light-proof mulch of plastic sheeting. This was then punctured to plant squash
plants or potatoes straight into the compost.

After four months or so the crops were ready for harvest and after six months the plastic
cover could be removed leaving a weed-free bed ready for planting or sowing, (my one
reservation was the plastic sheeting, which although quick and effective eventually goes to
landfill. Perhaps compostable cardboard could be used instead, covered with a further layer
of compost on top to hold it in place).
The principle of no dig was persuasively demonstrated throughout the talk. Then there were
the spontaneous asides that would prompt a flurry of note-taking on the backs of envelopes
or old supermarket receipts – whatever could be dredged from the recesses of a pocket in
time to catch the idea. These random pickings included:

Slug problems – reduce habitat : Raised beds do not necessarily need sides which provide
slug habitats, but can simply be mounded. Mulching with compost instead of straw or woody
material is less hospitable to slugs and more suited to wet climates like ours (wood-chip on
paths can be put on beds as mulch after 2 – 3 years when rotted down). Bring plants on in
pots where possible. Keep the growing area tidy and transplant seedlings when mature
enough and easier to protect.

Sow towards full moon not after.

Copper tools: Their use was first inspired by the Austrian visionary, forester and hydrologist
Victor Schauberger. Beautifully made, converts say they do something special to the soil and
also deter slugs.

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Persistent weeds such as couch grass and bindweed: Weaken the parent root by digging
down and removing where possible. Mulch will do the rest.

Visit the garden daily : “Gardeners are natural multi-taskers”. Short periods in the garden
regularly are better than long periods once in a while. Attend to weeds when young or lightly
hoe. Carry a compost bucket as you go for weeds and trimmings for the compst heap.

Salad leaves: These should be picked by hand, not cut with a knife.

Insects: Years ago when driving down a country road at evening time the windscreen would
become covered with insects. Now there are none. Be aware.

I ventured to ask his opinion on ‘biochar’ about which I have written several blogs. He said
he was ‘unconvinced’ (obviously about the many claims for its virtues) but conceded that it
could be a useful soil amendment. Having made an abundance of biochar last autumn from
extinguished bonfire cinders, which were then sieved and put through the garden shredder,
I have added liberal amounts to the compost mulch on my no dig beds. One great pleasure
of gardening is the accumulation of knowledge as time passes. I wait to see what the benefits
will be.

I came away from the lecture with a Charles Dowding 2017 Diary . Packed with photographs
and useful information, It is probably all you would need to get going on a no dig garden. On
the last page I found this quote: “It is a pleasure to offer this compendium of advice, based
on my decades of growing food and flowers. The plants keep telling me more, my methods
evolve, and a common factor is soil health.”

Suggestions:
www.charlesdowding.co.uk – See Charles Dowding videos on youtube
Wood-chip – Local tree surgeons are often looking for places to drop wood-chip for free.
Copper gardening tools: www.implementations.co.uk

By our Sustainable Blogger – Henry Brighouse


BIOCHAR, FOOD AND THE ENVIRONMENT

In previous blogs we looked at the benefit of adding biochar to the soil in order to improve it. Good soil makes healthy plants with good immunity to weather extremes, pest attacks and disease. Nature has been producing biochar since plant material existed. It is found in what was once some of the world’s richest soil, such as the prairies of the American Midwest (now covered from horizon to horizon with chemically induced, genetically modified corn and soya). Over the millennia wild fires would sweep through the dry prairie grasses leaving deposits of charcoal. This would become part of the soil structure layer by layer.

But good soil, with or without charcoal, essentially gets its fertility and structure from the biology that inhabits it. The first of our species who cultivated the soil learned to work with it. Thus was born agriculture, an almost sacred pursuit requiring a deep attunement with the cycles and rhythms of nature.

So what happened to agriculture?

Maybe it started with the machine age, but a turning point came when in 1945, a war-weary and hungry world needed a magic bullet to boost food production. The science of the day came up with NPK (Nitrogen, Potassium, Phosphorous) fertilizer. If you inherit good soil this will certainly give some impressive results. But the quick fix it should have been soon became an addiction with an insatiable appetite of its own. ‘The Green Revolution’ as it was called, turned agriculture into agri-business, and chemical-based farming became a world-dominating industry.

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Heavy machinery enabled the ripping out of hedges and trees, the filling-in of ponds and generally clearing the landscape to make huge fields for monoculture planting, whilst fleshy, fast-growing hybrid crops were developed to maximize yields. This combination formed an irresistible invitation to pests. With most of the wildlife habitats for natural predators now gone, a new market opportunity emerged for wholesale pesticide use. As profits for agri-business soared, the natural environment deteriorated, and even persuasive whistle-blowers like Rachael Carson in her early 1960s book Silent Spring remained largely unheeded.

Today, whilst in Britain we are still protected by EU regulation from the introduction of GM crops (although plenty arrives as animal feed), in America over 90% of all soya, cotton and corn crops, are patented genetically modified with pesticide-producing genes or genes that give resistance to herbicide. None of these crops can grow without heavy applications of synthetic chemicals. This head-on collision with nature has seen the rise of resistant ‘super-weeds’ requiring even stronger herbicides akin to the infamous ‘Agent Orange’. In the two decades up to 2013 over 2.6 billion pounds of Monsanto’s Roundup was used in the USA alone and its use grows year on year. To give a hint as to what this might mean, where the Mississippi delta meets the Gulf of Mexico, a ‘dead zone’ fans out for 5 miles where nothing lives due to pesticide residues – all this to produce quantities of nutrient-deficient food, and a very uncertain future.

USA, Kansas, Tractor in a field

The collateral-damage is ultimately us. Apart from the impacts on health from airborne pollutants from crop spraying, there are correlations between the decline in soil health and human health. When we hear that minerals vital for health such as selenium are no longer in the soil, it is not always that the mineral isn’t in there, it is just that the soil biology that made those minerals plant-available, and therefore human-available, is no longer there.

Food supplements can be bought almost anywhere, but the once living soil (part of our environmental ‘capital’), not being part of the money equation, has steadily been degraded to the extent that in many places, even here in our green and pleasant land, no amount of chemicals or clever science can increase yields or produce the food we need to stay healthy.

Biochar is not a quick fix in itself. It is one approach in an overall soil recovery strategy that will come sooner or later as, through necessity, we embrace an agriculture that is sustainable. Fortunately, the science of soil biology and soil recovery, as developed by pioneers such as Dr Elaine Ingham, founder of ‘The Soil Food Web’, make this possible.

A change in our collective consciousness to a more holistic approach to life is also happening as shown by our buying choices for what we eat and how it is grown. As agriculture responds the environment improves. People also seem to be more aware that everything is connected. And if we want to look further into it we will find that beneath our feet, a whole universe of purposeful and intelligent microorganisms can be summoned to work for us 24/7. It’s not only a free work-force, it is also a very large one. An estimated 90% of all organisms that inhabit the world’s land mass live underground.

Underground is also where we find one more persuasive argument in favour of biochar. The idea of locking carbon into the earth instead of sending it up into the air as greenhouse gasses is an appealing one, especially if it can help to restore the fertility of the soil at the same time.

Making charcoal requires heat, which produces CO2, a greenhouse gas, but by comparison, disposing of woody material with a bonfire will send 97% of the carbon locked up inside it into the atmosphere as greenhouse gasses. Allowing it to rot or composting will release 70% of the carbon into the atmosphere, whereas making charcoal releases only 50%, and some of that can be captured as bio-fuel. The other 50% remains behind as a stable form of carbon, where it can last in the soil for centuries or millennia.

Biochar as a viable means of carbon sequestration may always be a local undertaking because transporting large amounts of plant material for centralized processing would create more CO2 than it saves. So where would all the biomass come from? Certainly not from cutting down all the trees and turning them into charcoal. Apart from every other wonder concerning trees, trees themselves form a valuable form of carbon sequestration. But there is an abundance of plant-based material in agriculture left over after every harvest which can be profitably transformed into biochar: plant stems, seed husks, nut shells, wood from tree trimming etc.

Carbon Gold’s UK produced biochar, inoculated with fungi, seaweed and worm castings, has recently been used in a research project sponsored by the Bartlett Tree Research Laboratory and Reading University. Promising results show that when applied to the roots of ash trees, biochar makes them immune to the chalara virus, or ash dieback disease. This is important but not unexpected news and perhaps the science of the future will be focusing its attention on soil biology which, when given the right conditions, seems to know a lot more about plant health than we do. Biochar will inevitably be part of the equation.

 

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Biochar production as a back-garden hobby or farm-scale undertaking is the subject of numerous Youtube videos. Also on Youtube you can also find there some low-tech but inspiring biochar schemes in developing countries where efficient charcoal-producing wood-gas stoves have been ingeniously produced to replace open fires, a cause of so much environmental damage and disease, especially amongst women and children. One of these is the ‘Estufa Finca’ project in Costa Rica where the charcoal made by the stoves is bought back from households and resold in biochar form. It is giving natural approaches to agriculture a boost locally and also having an impact on reversing the damage to banana plantations from disease and over spraying. It’s fun to watch too (Link to Video 1 of 4).

Useful info about soil:
– Books: 10 steps to Gardening with Nature – Rollins, Ingham.
– Google: Bruce Allyn – ‘Healthy Soil Microbes, Healthy People’ June 2013

 


BIOCHAR AND THE SOIL

The secret of an ancient civilization that once thrived along the Amazon lay in their ability to transform the poor soils of the region into a magical substance known as the terra preta, or black earth. However much gold the Spaniards came away with, they missed this, the real treasure of El Dorado. Civilisations may rise with hoards of gold, but they fall when they lose touch with the earth. Today, wherever it is discovered, terra preta is prized by local farmers. Legendary for its stability and fertility, it is even credited with self-regenerative properties. Analysis has shown that a key ingredient in this soil is charcoal.

What is special about charcoal? If you can imagine folding a football pitch into the size of a golf ball (the trick is to make it very thin), then you would get an approximate idea of how much surface area there is wrapped up in a golf ball sized chunk of charcoal.

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Charcoal is an intricate matrix of minute empty spaces – pores, holes and channels divided by thin structural walls of pure carbon. It is produced when any plant-based material (usually wood but it could equally be corn husks, nut shells, plant stems…) undergoes pyrolysis, a burning process in an oxygen-starved environment that drives off all the volatile compounds. What is left behind is the pure carbon framework of the plant, charcoal.

Charcoal, like diamond, is a very stable form of carbon, and can last in the soil for hundreds or thousands of years. This gives it a certain unique status. Charcoal is negatively charged and attracts positively charged soil nutrients. Technically speaking this gives it a high ‘CEC’ or ‘cation exchange capacity’ (apparently a very positive feature). Being a long lasting form of carbon, it holds onto these nutrients for a long time, giving stability to soil structure, and fertility. It is also in this carbon labyrinth that beneficial soil microorganisms that process these nutrients find a safe haven.

What are these tiny microorganisms, what do they do, and why do they need a safe haven?

Agriculture covers 38% of our terrestrial planet. That means soil. But the hungry corporate machine that drives modern agriculture is not friendly to soil biology, and is destroying it. If the soil biology were to completely vanish we would be left with the sort of barren movie landscape reserved for the latest Mad Max film. Yet in some parts of the world such as the Loess Plateau in China, this has already happened. Although remedial work is already underway there, much needs to be done worldwide to rescue our soil. Biochar could play a significant role in this.

All healthy soils contain purposeful populations of living organisms (with some exotic names); bacteria, fungi, nematodes, microarthropods, worms and many more. Together they form an integral ‘soil food web’ and, apart from eating one another, accomplish amazing tasks. They transform the minerals locked up in sand, silt and clay into vital plant nutrients, convert fallen trees, leaves and other organic material into humus, regulate soil moisture content, transport nutrients to where they are needed and create a rich, intelligent, cohesively-structured growing medium for plants.

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Soil microorganisms also form mutually beneficial (symbiotic) relationships with plants, which exude specific sugars through their roots to attract them. These microorganisms in return deliver the right nutrients in the right quantity at the right time to the plant roots where they are needed.

Although much remains to be known about the precise mechanisms of biochar, as a soil amendment it has proven to be extremely helpful. But what makes it different from an ordinary piece of barbecue charcoal? Essentially it is the same thing, except in its preparation. The type of material used, and the temperatures and timings of the process, will produce some variations. Once made, the charcoal is broken into small pieces and ‘inoculated’ or primed with a compost (biologically rich) solution. Charcoal on its own would otherwise initially draw nutrients from the soil into itself, so the benefits for the first year would be delayed. The priming process gets the necessary biology started beforehand. At this point it becomes the ‘bio-char’ of the terra preta, ready to bring enlightenment to your soil.

In my next bog we will look a little more into the effects of agriculture and the soil, and the overall implications of widespread biochar use, and some very interesting projects. Are we going to burn all the trees to make biochar? Certainly not.

Useful info:
Youtube:  ‘The Secret of El Dorado – Biochar. Horizon
Youtube:  Dr Elaine Ingham ‘Soil not Dirt’.


THE DISCOVERY OF BIOCHAR

From Henry Brighouse our sustainable blog writer –

In the film ‘The Martian’, an astronaut (Matt Damon), stranded on Mars has to stay alive until another space mission from Earth can rescue him. His only option is to create soil, a biological medium in which he can grow food. All he has at his disposal are a few potatoes going to seed, a climate controlled tent, the discarded toilet bags of his departed comrades (definitely
biological), Martian dust and water. The story, naturally, has a happy ending.…

READ MORE