Page 16 - Simply Veg 3.21

The benefits of no-dig gardening
ELIZABETH MOONEY
Having noted several articles on digging in recent editions of the Simply Vegetables magazine, I am writing as a firm proponent of no-dig in an attempt to redress the balance. At its simplest, no-dig is a technique that involves leaving the soil undisturbed and covering it with a good layer of organic matter every year, leaving it to the worms and other soil organisms to incorporate this into the soil.
Until a few years ago I dug my allotment every year without ever really thinking about it because it seemed to be what the perceived wisdom suggested should be done. However, upon starting training as
a student at RHS Garden Wisley my view rapidly began to change. I am still a student there, now specialising in edible growing and am a strong believer in the benefits
of no-dig. The vegetable garden at Wisley has been no-dig for several years now and the new World Food Garden is also being created following no-dig principles.
No-dig is not a new idea. As far back
as the 1940s Arthur Guest was espousing not being a ‘slave to the spade’, and even wrote that he ‘had club root fairly badly
but compost treatment cured this in two years’. Also, in the 1940s, F. C. King, a head gardener in Cumbria, concluded no-dig controlled weeds better than digging and lead to healthier soil with more earthworms. In more recent times, Charles Dowding has done a lot to raise the profile of no-dig and push it more towards the mainstream.
So, what are the benefits of no-dig gardening?
• Higher yields: we all like our plots
to be as productive as possible,
and no-dig gives us that. Between 2013-2020, the comparison beds
at Homeacres (Charles Dowding’s garden) have produced 854.53kg
of produce from the no-dig bed and 754.81kg from the dig bed, with the same crops being grown in both, and the same amount of compost being given to each bed. No-dig areas can also be cropped more intensively as the soil is healthier meaning a smaller area is needed.
• Fewer weeds: when soil is
disturbed by digging weed seeds
are brought to the surface, and one way soil recovers from digging is by recovering itself with weeds. This does not occur in no-dig where
the few weeds that are blown in or brought in can quickly be removed.
If you have plenty of weeds when starting out, then try to remove woody weeds such as brambles before covering the rest with cardboard and a good layer of mulch. This will kill all but the most vigorous weeds in a few months, and after removing these and reapplying the
mulch annually, the weeds will be
under control within a year or so. • Better soil health: the beneficial
organisms and microbes in
the soil are more plentiful in
soil that is not dug. This is
because their home is not
disturbed and broken up
annually by digging, meaning mycorrhizal associations are
left intact and soil organisms
are more plentiful. Particularly
with reference to single-celled organisms, the no-dig soil at Homeacres has been found to support a stronger eco-system than the dug soil. Healthier soil helps lead to healthier, stronger plants, and means soil ameliorants and fertilisers are not needed. Charles Dowding applies no fertilisers of any kind to his beds and can still harvest three good crops from a bed in a single year.
• Better soil structure: every time you dig the soil you are breaking up and damaging its structure, whereas in fact plants root better in firm soil than in soil that is excessively loose. At Homeacres, a trial has shown that soil where the surface was loosened every year with a fork produces around 5% fewer crops than where this does not occur. Soil loosened by digging can also be more prone to erosion. There is evidence that the better soil structure in no-dig beds then improves root growth, and the structure of a no-dig soil means it can be walked on without causing compaction, unlike in dug areas.
• Less compaction: when soil is cultivated it can create mini layers of compaction. In no-dig the soil is better aerated with better gas exchange to the roots.
• Fewer pests: Compaction can result in the soil giving off some alcohol which attracts slugs, so the lack of compaction in no-dig soils means fewer slugs. Also, no-dig can lead to there being more beneficial insects present to control the pests as digging can disturb soil fauna that overwinters in the soil.
• Saves time and effort: it takes less time and effort to spread the compost on the surface of the soil than it does to dig it in.
• Less watering, better drainage:
no-dig seems to need less watering as the water sinks into no-dig better than dug beds and the better soil structure holds the water better. Also, there is less moisture loss as moisture is lost from the soil when it is dug.
• Better carbon capture: our soils
hold huge amounts of carbon, but when the soil is dug it is exposed to the air and released as carbon dioxide. The carbon reservoir in our soil is often overlooked in the battle against climate change but should not be underestimated.
The most common criticism I hear levelled at no-dig is that it requires too much organic matter. This is not true. To grow healthy plants the soil needs plenty of organic matter, whether dug in or not. In fact, many no-dig advocates say that no-dig actually needs less compost. In the 1940s Arthur Guest stated he used 40% less compost
in no-dig than he had in digging as the soil organisms were healthier and therefore
the compost was being used to maximum advantage. A gardener may have difficulty getting hold of the organic matter needed, but to grow the best crops this is a problem with both dig and no-dig.
Since I have been practicing no-dig I have found all the above benefits bear this out in real life. Weeds on my allotment are vastly reduced, and when I did a trial for a year of digging part of my plot and doing no-dig on the other, the difference was clear. Even in the really hot weather of last summer, none of my plants wilted or seemed to struggle from drought, despite me not watering as often as I thought I would need to. The labour saving has been huge and is much appreciated as I work full time as a gardener anyway.
It is my belief that no-dig is better for the soil and therefore better for the plants, and I would encourage everyone to try it out, after all, don’t we all want to use the technique that produces the best results?
For more information on no-dig, please see this website: https://charlesdowding. co.uk/
I recommend looking at Charles Dowding’s YouTubes as they are interesting. So now you have both sides of the debate and can decide whether to dig or no-dig! - Ed
16 Simply Vegetables