Magically, it was in this renewed phase that I found a method to grow vegetables that I could just ease into. It was also the simplest way to feed us and do good for the planet. A dear old friend from my past life posted on social media his no dig polytunnel with a reference to
Charles Dowding. It seemed too simple to work, nothing I had heard of before in all my reading and viewing, and contradictory to anything I’ve done or know or read about growing plants. How do you sow a plant if you don’t dig a hole in the ground?
So how do you do no dig? You will need to stop reading or listening to this and go outside with all those Amazon cardboard boxes you have. Strip off the packaging tape – chemicals make it sticky, and you don’t want that leaching into your plants and into you. I get my cardboard from my local pet store, pharmacy, and grocery stores.
Lay the cardboard flat on to your lawn or weedy ground. Overlap the edges so that no light gets through to the ground below. You are killing weeds through light exclusion. At this point you can water the cardboard to make it less rigid. If, like most of us, you have a lawn of invasive Kikuyu grass , fear not and dig not. Then pile on 6 inches of compost directly on top of the cardboard. You don’t even need sideboards – you can create a mound. Then you do the no dig dance. Before sowing seeds, if you are feeling free and breezy in the garden, gently step, walk, shuffle on your beds to the musical beat of the tweets, chirps, chirrups, whoops and bass buzz tunes of the birds and bees. The structure of the undug soil is so good that stepping on it doesn’t compact it – dispelling another myth – that you should not walk on beds. Well, you can on a no dig bed.
After your bed looks level and inviting, make a hole with the back of a trowel and stick your vegetable saplings deep in or directly sow large seeds (okra, corn, beans etc) and water. Multi-sowing is another technique that works so well in no dig beds. I multi-sow beetroots, onions, leeks, knol khol, lettuce, rocket, spinach, and table radish. Multi-sowing saves time, effort, and space in the garden. Compost is reapplied on the surface of the no dig bed once a year, about an inch thick layer.
So, here’s what you are really doing alongside the steps above. That weedy lawn grass is slowly going to die because of light exclusion from the cardboard. If you lift up the cardboard from the sides, you will see very pale yellow and white grass dying and adding organic mulch to the soil. You are inviting all the bacteria and fungi to return as the grass decomposes. The wet cardboard will attract legions of earthworms who will break it down, turn it around, doing the boogie-woogie and shaking it all about, adding organic matter and structure to the soil below. The compost is going to enrich all of this while providing a deliciously rich environment for your plants. It is a myth that compost is too rich for saplings.
A word on compost and its edaphic properties. Compost is not soil. Compost is decomposed organic matter ranging from recognizable plant parts (roots, leaves, stems) to humus, which is partly decomposed plant material that is amorphous, aerated, and spongy in nature. Organic matter contributes to a soil’s ability to retain nutrients and water. It aids in holding nutrients because negatively charged compounds in humus attract and hold positively charged plant nutrient ions. It helps provide water because humus can absorb 80-90% of its weight in water and therefore contributes to a soil’s ability to hold water under drought conditions. My no-dig beds require a good drenching only in the dry winter season and have survived unscathed even after heavy monsoon rains. This is completely unlike the compacted soil most of us have in the garden–where soil remains airless, comparatively lifeless, and where water can hardly soak in or drain. Everybody can start making their own compost. A number of kits for small and large spaces are ready to use or you can set up your own system to make hot compost that also kills weed seeds.
You are going to have a lot of questions about no dig (and composting) as you unlearn what you know of traditional food gardening that requires you to dig and plough. Such as, can the plant roots grow through the cardboard? Will my carrots and parsnips go all squiggly at the end, will they fork? Will no dig work in hard, clayey, compacted soil, filled with gravel?
My garden is covered by invasive Kikuyu grass growing over construction debris making it lumpy and uneven. But by mulching the soil with compost, I have created a healthy growing environment and improved the less than healthy soils below, which had no doubt been sprayed with chemicals and tilled for decades. The simplest ideas are sometimes the greatest. No dig can be applied to any climatic zone, soil type, for home or market garden purposes. It is easy on your back. You don’t have to dig a vegetable or flower bed ever again.