NOT DIGGING IT
There’s a form of garden that, once created, demands to be left to its own devices to deliver the goods to your crops.
No-dig gardening has a very attractive ring to it – and so it should. It provides beds that are easy to manage and rich in nutrients. Well-constructed, the method sees a garden with the ultimate soil structure that requires little, if any, weeding, and which is quick to warm up and free-draining. Depending on the size, situation and available materials, it can be created in a day. Sounds inviting? It is! But, before you begin, read on.
SIZE MATTERS
Unless you have a tractor at the ready to shift loads of the sorts of materials required to build a no-dig garden, the size of your growing bed will need to be kept small. For some growers, this isn’t an issue, but if you’re wanting to feed a family rather than just yourself, you can still choose to enjoy a small no-dig in an experimental way. In this case, use it to grow special, high-value plants such as strawberries and asparagus, or shallow-rooted plants such as tomatoes and lettuce that benefit from the extra goodness and structure a loose, high-nutrient garden provides.
NO GROUND? NO WORRIES!
If you live in a situation where there simply isn’t any ground for a garden, a no-dig is your answer. It can be built directly on solid surfaces, such as concrete or asphalt, or in a garden pod (a container garden on legs). A no-dig can even be built in plastic tubs or wooden boxes. The only consideration is where the moisture from the beds will flow to, and if it might stain the surfaces beneath your no-dig.
NO-DIG GARDEN CONSTRUCTION
Building a no-dig garden is similar to creating a compost pile:
• Start small (no-digs take a lot of filling!).
• Choose a level(ish) area for your garden. It can be on the ground, on a solid surface such as concrete, or in a large container with drainage holes in its base.
• If building on the ground, mow the area first, then lay down a weed-barrier base (this can be a thick layer of wet cardboard, or weed matting).
• On top of the weed barrier (if you’re not using a container), create an edging that will keep all the fill in place.
Construct your edging from bricks, rocks or untreated, unpainted wood.
• Fill the no-dig area with 10–15cm layers of the following materials, thoroughly wetting each layer before adding the next, and repeating the layering at least twice (note: if using a container, adjust the depth of layers so the materials fit the container): grass clippings, autumn leaves, watersoaked non-toxic newspaper or cardboard (if using), straw, and animal manure and compost (combined).
• If you want an instant no-dig garden, make the final layer of compost at least 20–30cm deep.
• Let the final layer of the bed be a mulch, such as straw or pine needles.
• If you are not in a hurry, leave the materials to settle for four to six months, topping up with compost after settling has occurred.
• No-dig gardens are free-draining. Keep a close water watch on them during the warmer months.
TOXIC – TRUE OR FALSE?
Newspaper and cardboard are often used in nodig garden construction, but debate is ongoing as to whether or not it is safe to do so. In the end, it comes down to personal choice. Let this be an informed choice by doing your own homework on the subject.
Newspaper, which is made from wood pulp, is certainly biodegradable – in fact, worms seem to head for it when it is incorporated into the compost pile or a no-dig garden. Worms, and a range of soil microbes, break down the paper into cellulose, releasing carbon, an essential in healthy soil, into the garden. So far, so good, but what about the chemicals that go into bleaching the newspaper?
If whitening the paper pulp has been achieved through the use of chlorine bleach, this product eventually, and very slowly, leaves behind traces of the highly toxic chemical dioxin. If the whitening chemical used is hydrogen peroxide, the outlook is brighter as it eventually breaks down into oxygen and water.
As for the ink used to print newspapers, in the past it was composed of worrying heavy metals such as lead and cadmium. Newspaper ink is now more likely to be made from soybean oil, and so is more garden-friendly – but that’s not always the case, so, what is a no-dig gardener to do?
Believe it or not, companies actually welcome enquiries from the public about the products they use, so check out the ingredients that go into the making of the newspaper you intend using in the garden by emailing or phoning the printer. Do the same with any cardboard you are considering using, so you are aware of any bleaches, glues and inks used in its production.
If you have any doubts about using newspaper or cardboard as part of your no-dig garden ingredients, leave them out!
PERENNIAL WEEDS
Even the most stubborn perennial weeds will eventually give up the ghost if deprived of light. But light deprivation needs to continue for at least a year if this is to be the case. And weed invasion from garden edges also needs to be managed. Achieve light deprivation by ensuring that whatever base you lay down over the weeds is thick enough to resist complete decay for at least a year. You may, for instance, use weed matting in conjunction with non-toxic cardboard, or a triple layer of the latter.
WHAT CAN I GROW IN MY NO-DIG GARDEN?
If you are happy to wait several months for your garden materials to decompose and settle, and if you then have enough fill for a bed that is 30cm deep, you can aspire to grow root vegetables such as medium-depth carrots, beetroot and potatoes. This depth of garden will also support leafy vegetables, such as brassicas and silver beet, which enjoy a deeper, cooler root zone.
If you want to grow in your no-dig garden immediately after constructing it, you should aim to grow shallower-rooted vegetables, such as salad greens, smaller varieties of radish, leeks and spring onions.
REASONS TO LOVE NO-DIG GARDENS
1. Growing with the goodies
A regular in-ground garden is formed using existing earth to which all the garden goodies must be added: fibre, nutrients, and compost. In this situation, it’s easy to get careless. Your garden can become no more than unproductive dirt if you haven’t been vigilant about adding the necessary ingredients. With a no-dig garden, your growing medium is always in the best of health because without the goodies, it wouldn’t exist.
2. Loving the life beneath
There’s no getting away from it – soil disturbance is a killer. The moment you go digging around in the earth, whether it’s with a rotary hoe or a fork and spade, you are disturbing the beneficial micro-organisms in your soil. Sure, they will reorganise themselves, but while they do so your plants are served with a setback. In terms of providing a safe-zone for your soil organisms, a no-dig garden is the answer.
3. Rainfall And run-off
Any raised garden, including a no-dig one, runs the risk of being water-hungry as gravity sends the water down to its lowest point. But because a no-dig contains loads of moisture-retaining materials (such as straw and compost), gravity has a fight on its hands. A no-dig is also without the hard crust that so often forms on the surface of a regular garden, and which results in much of any moisture it receives running off, rather than passing through, the growing medium.
IS NO-DIG GARDENING really LABOURSAVING?
As an alternative to the slog of digging up the ground with a spade and fork, or wrestling with a rotary hoe, no-dig gardening can at first seem to be a labour-saver, but is it really? Given the amount of material that must be sourced from off your property, and carted in, probably not. However, while there’s no getting away from the back-work involved in digging or hoeing, a no-dig affords the opportunity to carry light loads, bit by bit, onto your construction site over any period of time you choose. On top of this, a no-dig garden can, over time, be raised to a height that will be more manageable if you have a back that does give you problems.