Table of Contents
- 1 How to Create a Successful No Dig Garden?
- 2 Sourcing Materials for Building No Dig Gardens
How to Create a Successful No Dig Garden?
There are many variations and techniques for using No Dig Garden method. This is just one suggested approach based on our experience and research and Toby’s recommendations.
Ideally, this new garden bed should be prepared in the autumn and left to decompose over the winter. If you use this technique in the spring or summer and plant immediately, it works better if you have more carbon layers and more compost/soil mix and fewer nitrogen layers (see # 11 below). If you plant soon after making the new bed, or the material hasn’t decomposed much, make furrows or pockets in the top layer of mulch and fill them with compost and soil mix and plant directly into this. This will enable the seeds or plants to grow while the sheet mulch is decomposing below it. It is generally easier to grow established seedlings in a new no-dig garden rather than direct sowing of seeds. Root crops like carrots and beetroot don’t do well in new beds.
If you do plant immediately, don’t expect high yields the first season because the material hasn’t broken down enough to provide many nutrients for the new plants or seeds. Organic substances decompose when micro-organisms consume this material. It is only when these micro-organisms die that plant nutrients are released back into the soil in a form which the plants can use.
Building high quality, healthy soil is probably the most important thing we can do for our garden and is essential for growing healthy plants which produce vegetables with high nutritional value. But it does take time to practice patience and slowing down to the speed of nature. Don’t be afraid to experiment with different materials. All organic material breaks down and produces soil. Your new garden needs air, water, nitrogen, and carbon.
For No Dig Garden Try the Following Steps:
- Mark out the area for the garden with string or boards which is preferably level and running east to west for best sun access and allows the use of trellises on the south edge for vertical gardening which won’t shade the garden. Put the garden as close to the kitchen as possible. Make sure the area gets 6-8 hours of sun. We suggest you start small at first- perhaps even one square meter. Don’t make it any wider than you can reach halfway across from the sides. Some prefer beds no more than 75cm wide for ease of straddling or stepping across. Garden paths should be ~30cm wide for walking or ~100 cm wide if you want to use wheelbarrows.
- If the new garden area is heavily compacted soil (old parking area, etc) push a spading fork into the ground and rock it back and forth and do this over the entire area before laying down the new bed to encourage root penetration and drainage. It is also important to try to remove invasive plant species because they can travel laterally, emerge from under the sides of the bed and then reinvade your bed.
- Some prefer to put in edging material like boards which will contain the soil when it is built up. If so, we suggest using untreated lumber, perhaps stacking two 2×6’s on edge, and only use painted wood if lead paint was not used. Use short sections of used pipe, rebar or stout wooden stakes on the outside to hold them up.
- Gather all the bedding materials together for the layering process before you start if possible.
- It is very important to wet down the soil thoroughly before building the new bed, if it is dry, to prevent the ground from sucking moisture out of the bed of new materials.
- Cut down any grass or non-invasive weeds and lay them on the ground or stomp them down.
- Add soil amendments if desired to help with plant growth. See section on soil amendments at the end.
- If no grass or weeds are on soil, put down a thin green layer of fresh grass clippings, manure or vegetable scraps on the existing soil surface. This will help to rot any turf underneath. Fresh manure works best but aged manure should be used if you intend to plant in the garden soon. Water grass or manure if dry.
- Add worms if you have any. They will do much of the work to break down the organic material.
- Cover the garden area with thick layers of wet newspaper (not shiny or colored) or preferably use 2-3 layers of wet cardboard, with plastic and staples removed, to smother any weeds. Overlap the paper or cardboard so there are no gaps for weeds to grow through. Water both sides of the cardboard just before laying it down, so it will decompose quickly or you can leave the cardboard out in rain beforehand or a 3-5 minute dunk into a big plastic trash bucket of water works best to get water inside the cardboard. Cutting the cardboard into pieces ~ 60 cm squares is a good size for dunking.
- Alternate thin layers of green (nitrogen rich) and thicker layers of brown (carbon-rich) and water each layer. The green layers should be grass clippings which haven’t gone to seed (preferably cut in the previous 24 hours to avoid getting slimy) and are not sprayed, or fresh weeds preferably without seeds, manure, food scraps or seaweed. The brown layers are a shredded newspaper, junk mail (not shiny or plastic), dry leaves, dry grass, unsprayed straw or spoiled hay. Strive for maximum diversity of materials. The total depth of these layers should be 30-60 cm to build soil fertility. It will settle down to one-quarter of the depth as the material breaks down. Try to create a plateau, not a mound, which could shed rainwater
- Add 5-10 cm of compost, soil, or compost and soil mix. This is the layer you will plant in now or later.
- Cover the area with at least a 5-10 cm layer of loose straw which shouldn’t contain seeds. This allows oxygen into the soil, prevents compaction and keeps under layers shaded and moist. Make sure the straw hasn’t been sprayed with pesticides. Water the straw lightly. Avoid using hay which contains seeds and packs down and can become anaerobic and acidic. If grass does grow from hay or straw, it can be easily pulled out in the spring or chopped into the soil. Leaves can also be used as a top layer. If you have high winds in your area, you may not want to use a final layer of straw or leaves or you can cover it all with netting.
- As this new soil structure is immature, the bed will need regular watering during dry periods.
- Avoid stepping onto your new garden beds whenever possible because this compacts the soil and makes it more difficult for roots and oxygen to penetrate. Provide paths, boards or stepping stones to walk on.
- Drip irrigation and a water timer can water the bed effectively if you don’t have time to water as needed.
- After each season, it helps to add new layers of organic material to provide fresh nutrients to the soil.
Soil Amendments to Add
In addition to, or instead of manure, which provides nitrogen, one can add blood meal (‘Blood and Bone’).
Gardens are often deficient in phosphorous which can be helped by adding rock phosphate dust or bone meal.
Add some green sand or rock dust or loose clay to the garden to add various trace minerals.
Most vegetables function optimally in a pH range of 6.5-7, slightly acidic. It is best to periodically test one’s soil. Inexpensive testing kits are available at local nurseries. If the soil is too acidic, add lime lightly. If it is too alkaline, add sulfate of ammonia.
Use of Plastic
Do not use plastic sheeting or weed mat under the mulch because it will prevent plant roots from penetrating it and will not allow nutrients or worms to move freely in the soil. We also discourage the use of plastic on top of the mulch because it sheds rainwater and off-gases toxins when it heats up.
Most gardeners come to realize the importance and value of adding high-quality compost to the surface of their gardens each year mixed into the top layers of soil before planting. Therefore, we recommend learning how to create a separate compost pile on your property which will enhance your soil fertility.
Benefits of a No-Dig garden
- Easy to learn and do- you can set up a small garden in an afternoon yourself.
- Low cost- most materials are free and readily available
- Minimum of effort with no digging involved unless present soil is heavily compacted
- Doesn’t disturb worms, microorganisms or fungi in the underlying soil
- Doesn’t bring up buried weed seeds to the surface where they can germinate and grow
- A thick mulch of organic material:
- Ideal for doing together in neighborhood groups which build community and is fun.
Reasons to Replace Part of your Lawn with a Food-Producing Garden
- If you grow an organic garden, it improves food quality and safety because commercial crops contain toxins from pesticides and herbicides.
- Precious water is used to grow food instead of on non-productive grass.
- Less money is spent on food and gas since there is less need for shopping for food
- You get more nutrition since food is fresher. This results in better health and more energy, which also lowers family medical bills
- No waste of food scraps, leaves or grass which can be composted into plant food.
- Food security is high if gardens are in your own back yard. Less chance of stealing.
- A medium sized backyard garden can produce a large quantity of food each year.
- Sharing produce and gardening with neighbors is fun and builds good relationships
Sourcing Materials for Building No Dig Gardens
- – Barley straw
- – Leaves
- Find under nearby trees, rake and bag them. Also, look for bags of leaves each autumn in your neighborhood. Ask your neighbors to save them for you. Most people gladly give them away because it saves them the cost of disposal. Check bags from others for content. Make sure there are no trash, gravel or pine needles in them. Best leaves are those which have been mowed and ground up and mixed with grass clippings. Note: Do not use leaves collected from gutters next to roads due to the potential for contamination.
- – Grass clippings
- Save your own and ask neighbors to save theirs for you. Don’t use clippings which have been sprayed in the last month. Smell it. If it smells like chemicals, don’t use it. Try to use it within 48 hours to optimize nitrogen benefit and before it turns slimy, smelly and anaerobic. Use them during the growing season between plants on your garden to shade the soil and feed worms. Also, use it on no dig beds or in your compost piles. Ask lawn services guys working in your neighborhood. They will usually give you clippings or drop them off at your house. Nelmac does this too (but check with them first to ensure they don’t come from sprayed areas). If you won’t use them for a few days, spread them out on a tarp to keep them from getting slimy. Don’t lay grass clippings more than about 5cm thick, as they will start to become anaerobic and smell bad.
- – Cardboard
- Large boxes from furniture, appliance and bike stores are the best source and have the least wrapping tape and staples to remove. There are usually bins behind the stores. You might also keep your eye out for cardboard on trash pick up day by the roadside. Cut down to ~ 60 x 60 cm. Make sure you remove all plastic tape before using.
- – Soil and compost mix
- – Seaweed
- Rake and bag it from Tahunanui beach after a storm. Rinse off sand and salt before using.
- – Worms
- Look around for local sources for red wiggler or tiger worms or see if friends can spare some from a worm bin. Another source is bags of horse poo which often have these type of worms in them.
- – Horse manure
- Look in Buy/Sell /Swap for free manure or stop at local horse farms and ask for it. They will almost always give you some for free. You can also get small quantities in bags or borrow a ute or trailer or pay a small fee for delivery of a larger quantity. Use fresh manure to make ‘hot’ compost piles. The heat will help kill pathogens and weed seeds. For no dig gardens, use aged manure (one year or older) as a base layer. Straw and manure mix from horse stalls can be useful in compost piles too.
Used timber for building raised beds or cold frames look
- for long, straight, nail-free, untreated timber. You can stack 2×6’s or 2×8’s on edge and hold them up with used pipe, rebar or metal posts.
- – Garden tools
- Garage sales are the best source of inexpensive wheelbarrows, shovels, garden, and leaf rakes and hoes.
an excellent source is Paul’s organic garden stall at the roundabout (Waimea and Beatson) -open Friday and Saturday. Otherwise Bay Nursery, Down 2 Earth, Mitre 10, Bunnings, etc. Waimarama Gardens (up to the Brook Valley) also sometimes has seedlings available.
An Extra Note: If you are planning to do a trip to pick up any materials, why not consider asking your friends and neighbors if they want anything – that way you can combine resources to make trips more pleasant, cheaper and energy-efficient!