Page 18 - Simply Vegetables Autumn 2021

Letters
The Benefits of No-Dig Gardening
I have just read the above article in the Sumer 2021 issue of Simply Vegetables and I feel that I must make some comments on it. May I say straight away that I have been practising
this approach for 8 years now and I am an extremely strong advocate of the no-dig approach and I sternly encourage a lot of new plot holders on our allotment site to practise it. I have even conducted a small experiment comparing the no-dig approach with the digging method.
However, my main concern with
the article is that although the author makes a number of assertations she does not offer any scientific evidence to back up her claims. For example, she states that no-dig leads to less compaction and the soil is better aerated. Where is the scientific proof of this? What papers have been written to research it? When I began my own
little experiment comparing the two approaches, I asked the RHS if they knew of any scientific research had been published on this aspect. They could not name or quote any research on this topic at all. If there is any, I would be pleased to hear about it so that I could read it for myself.
In actual fact the only piece of research into the no-dig approach I could find was one called “H.D.R.A No-digging report No 1, 1969” by J.L.H. Chase published by Lawrence D. Hills of Garden Organic. Unfortunately,
no one seems to be able to find this report, so I haven’t read it. It seems they did the no-dig approach for 7 years but then had a fertility crash. I cannot confirm this as I have not read the report.
Your correspondent also claims that no-dig leads to fewer weeds, I can confirm that this is generally true but I have a word of warning – make sure that the compost / manure you use is weed free and of a good quality. This year all my dig beds (7) are virtually weed free; of my 7 no-dig beds 3 are weed free and 4 are very weedy. My weed free no-dig beds had my own compost whereas the 4 weedy no-dig beds had manure from an outside source spread over them. I know the weeds came from the manure because the weed roots were attached to it.
What I can confirm is that the no-dig beds seemed to be healthier in that over the three years of the experiment the soil bacteria, protozoa and fungi had increased, whereas in the dug beds they had not.
So, can I end my by making a plea that if anybody else writes about the benefits of no-dig could they please back up their assertions with hard and fast peer reviewed, scientific evidence which has been published in reputable scientific journals. So far, I have not found any, may I close with that if the author of the article knows of any such papers could she please tell me so that I can obtain them. Do not tell me to read Charles Dowding’s books as I have read them all as well as the ones by F.C. King, Ruth Stout and Gerard Smith, as well as attending two of Charles Dowding’s courses and receiving his monthly newsletters. John Negus
Dear Editor,
There it was behind the door when I got home, Simply Vegetables and full of interest as well as Ms Mooney’s article on no-dig growing, the ongoing debate on no-dig continues. Is it the best way to grow and achieve good results, how can it be resolved? Philosophy is stepping back to think about your aims, what results do you want? To dig or not to dig, aye that is the question whether it is better to dig or not or suffer the consequences of digging instead (back ache).
Children use philosophy when learning, Daddy “why do cats have tails?”, “To balance” replies daddy, “What’s balance daddy”, your teas ready! Applied to Ms Mooney’s article, how is no-dig superior to digging, what is your evidence to support this in say horticultural writing or just doing it? Did it give better results?
Christine Walkden in her book ‘A Year in Christine’s Garden’ describes a no-dig way of making seed beds with a fork pushed into the ground to about 3” (75mm) over the bed, trodden to firm, raked to remove stones and weeds, then raked to provide a tilth. Water if dry and apply Growmore fertiliser and rake in then cover to warm the soil and sow the seeds next day. Or is it worth going one step further and buy plug plants from one of the suppliers when all the work is done for you and you just have to plant them!
On a totally unrelated point the water in hosepipes can be contaminated with the fatal Legionnaires disease. Some years ago, this was found in a hospital water tower and there were fatalities. Hoses, if left in warm sunny areas, allow the bacteria to breed; apparently this does not happen in watering cans. This is enforced in Bristol, details on the internet.
Roger Clements, Midlands Branch
Re Elizabeth Mooney’s article
If, as stated the benefits of no dig gardening were being espoused in the 1940’s it begs the question of why the method hasn’t been more widely taken up. Especially as by and large we gardeners are all looking for the easiest way of doing things.
I would suggest that some of the following points may be in play in relation to a 10-rod allotment plot i.e., 275.6 square yards.
The amount of cardboard required to cover it- 275.6 sq. yards. (230.4 square metres)
The amount of manure/ compost to cover it at 4 inches (10cm) deep- 30.6 cubic yards
(23 cubic metres) or approx. 214 barrow loads. I would suggest that this is at least 4 times the amount that is applied when digging and would explain any increase in fertility / yields.
Bindweed (convolvulus) thrives and spreads rapidly under a layer of mulch. Regular digging and careful removal of the roots is the only way to control an infestation. James Styles
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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.
mulch annually, the weeds wŠl be
UntŠ 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
organisms and microbes in
the soŠ are more plentiful in
soŠ that is not dug. This is
because their home is not
disturbed and broken up
annually by digging, meaning mycorrhizal associatÚns are
left intact and soŠ organisms
are more plentiful. Particularly
with reference to single-celled organisms, the no-dig soŠ at Homeacres has been found to support a stronger eco-system than the dug soŠ. Healthier soŠ helps lead to healthier, stronger plants, and means soŠ amelÚrants and fertŠisers are not needed. Charles Dowding applies no fertŠisers of any kind to his beds and can stŠl harvest three good crops from a bed in a single year.
a student at RHS Garden Wisley my view rapidly began to change. I am stŠl 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.
hold huge amounts of carbon, but when the soŠ is dug it is exposed to the air and released as carbon dÚxide. The carbon reservoir in our soŠ is often overlooked in the battle against climate change but should not be underestimated.
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 soŠ with more earthworms. In more recent times, Charles Dowding has done a lot to raise the profŠe of no-dig and push it more towards the mainstream.
• Better soil structure: every time you dig the soŠ you are breaking up and damaging its structure, whereas in fact plants root better in firm soŠ than in soŠ that is excessively loose. At Homeacres, a trial has shown that soŠ where the surface was loosened every year with a fork produces around 5% fewer crops than where this does not occur. SoŠ loosened by digging can also be more prone to erosÚn. There is evidence that the better soŠ structure in no-dig beds then improves root growth, and the structure of a no-dig soŠ means it can be walked on without causing compactÚn, unlike in dug areas.
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 soŠ 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 soŠ 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.
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 soŠ is healthier meaning a smaller area is needed.
• Less compaction: when soŠ is cultivated it can create mini layers of compactÚn. In no-dig the soŠ is better aerated with better gas exchange to the roots.
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 wŠted 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.
• Fewer weeds: when soŠ is disturbed by digging weed seeds
are brought to the surface, and one way soŠ 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 wŠl kŠl all but the most vigorous weeds in a few months, and after removing these and reapplying the
• Fewer pests: CompactÚn can result in the soŠ giving off some alcohol which attracts slugs, so the lack of compactÚn in no-dig soŠs means fewer slugs. Also, no-dig can lead to there being more beneficial insects present to control the pests as digging can disturb soŠ fauna that overwinters in the soŠ.
16 Simply Vegetables
under control within a year or so. • Better soil health: the beneficial
• Saves time and effort: it takes less time and effort to spread the compost on the surface of the soŠ than it does to dig it in.
It is my belief that no-dig is better for the soŠ 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 informatÚn on no-dig, please see this website: https://charlesdowding. co.uk/
• 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 soŠ structure holds the water better. Also, there is less moisture loss as moisture is lost from the soŠ when it is dug.
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
• Better carbon capture: our soŠs