No dig advantages
Most soil already has a good structure for plant roots to grow, and is full of growth-promoting organisms, which actually do not work so well after being disturbed. Millions of fungal threads, earthworms, millipedes and amphibians, to name but a few, are being helpful right under our feet. Soil is a living universe, ready to grow great plants when we help and encourage it.
Advantages of no dig
- Moisture is not lost by cultivations and is available to considerable depth, because there is no ‘shatter zone’ caused by the breaking of surface soil.
- Mycorrhizal fungi stay intact, so they are able to help plant roots to find more nutrients and extract more moisture: they are smaller than roots and can reach into tiny crevices
- You have better access to your plot and crops in wet weather, because drainage is good: the soil’s structure has not been broken by tools or machinery, water runs away and you can garden when you need to. I hear many reports of no dig allotments being not flooded while the dug ones are.
- Fewer weeds germinate, because their seeds are not exposed to light during cultivation, and because organic matter on the surface (instead of dug in) is a weed suppressing mulch.
- Soil is warmer in winter because deep-level warmth rises up, unhindered by structural damage from cultivations: my gardens have always been admired for their early harvests.
- You can quickly resow or replant at any time of year, with no soil preparation needed, after you clear a preceding crop of any surface debris, leaving its roots in the soil. So your season of harvests is longer.
What about loosening with a broadfork?
Some gardeners and growers use this, with good results, and without inversion of soil.
I have tried it on clay soil, and saw little or no difference in growth. At Homeacres, a four year trial of the same vegetables in forked and unforked soil shows slightly lower yields on the forked beds.
Where soil structure has been squashed and broken by machines, forking is worthwhile, then mulch with organic matter and leave soil life to reestablish the structure.
From Louise Tuffin, Devon UK, June 2016
“I am a no dig grower on my allotment. I have a business and work 6 days a week so needed a less time consuming method of growing, initially to clear a very out of control allotment, and then to grow produce for my tearooms. No dig is the only method where I can crop a good area without exhausting myself.”