Gardening would be way more fun, and many people would be more inclined to take up gardening if there wasn’t the need for all that back-breaking hard work such as digging… It may be a surprise to many people, but digging is NOT a necessary part of gardening at all!
A complex, symbiotic relationship exists between the soil surface and the underlying micro-organisms, which contributes to a natural, healthy soil structure. The soil is a mini ecosystem breeding billions of microorganisms like Bacteria, Actinomycetes, Fungi, Yeast, Protozoa, Algae and Nematodes. Furthermore, there are arthropods and insects in there as well, including earthworms. Digging into the bed can interfere with this process and disturb the natural growing environment. It can also cause soil compaction and erosion, and bring dormant weed seeds to the surface where they will sprout.
With ‘no-till’ gardening, once the bed is established the surface is never disturbed. Amendments such as compost, manure, peat, lime and fertilizer are ‘top dressed’, i.e added to the top of the bed where they will be pulled into the subsoil by watering and the activity of subsoil organisms. Weeding is largely replaced by the use of mulch. By adding material in layers, the underlying soil surface remains spongy, making it easy for the young roots of newly planted seedlings to work through the soil. This is similar to the way soil is formed in nature.
Benefits of no-till gardening
- Promotes natural aeration and drainage : Worms and other soil life are important to healthy soil structure, their tunnels providing aeration and drainage, and their excretions bind together soil crumbs. No-till systems are freer of pests and disease, possibly due to a more balanced soil population being allowed to build up in this comparatively undisturbed environment, and by encouraging the build up of beneficial soil fungi.
- Saves water : Thick layers of mulch allow water to pass through easily while shading the soil. This reduces water lost to evaporation while maintaining a moist growing environment beneficial for root growth.
- Reduces or eliminates the need to weed : Most garden soils contain weed seeds which lay dormant until the soil is disturbed and the seeds become exposed to light. With no-till gardening, these seeds will remain dormant indefinitely.
- Saves time and energy : Digging to turn garden beds is strenuous as well as time consuming. After applying the mulch during the growing season, no digging or turning of the soil is required.
- No-till gardening helps soil retain carbon : Healthy topsoil contains carbon-enriched humus and decaying organic matter that provide nutrients to plants and maintain the carbon-dependent nutrients essential to healthy crop production. Tilling the soil speeds the breakdown or organic matter, which releases nutrients too quickly. A steady, slow release of nutrients is more beneficial to plant growth.
- Builds earthworm population : The moist conditions of the soil beneath mulch creates the ideal environment for earthworms, whose activity aerates the soil and stimulates root growth.
- Helps reduce soil erosion: A lack of carbon in soil may promote erosion, as topsoil and fertilizers are often washed or blown away from garden beds.
Methods used in no-till gardening
Prepare the bed before adopting the no-till method: Loosen the soil and remove any rocks, roots and other obstructions. Remove any perennial weed roots and work into the soil materials like peat, lime, vermiculite, compost or other organic material.
- Use mulch liberally, in layers :Mulch is an essential part of no-till gardening. A thick layer of mulch will keep the soil from drying out and crusting over, which restricts nutrient and water flow to the subsoil. It also reduces water loss due to evaporation. Mulch provides cover for soil insects and often dramatically increases the earthworm population.
When planting seedlings, pull the mulch back and dig into the surface just enough to set the plant :The depth of mulch can be only a few inches when seedlings are first planted, then added in layers as the plant grows. Pull mulch away from the stems of tomatoes, peppers and long-stemmed plants to prevent stem rot.
The following lists common materials used for mulches:
- Grass Clippings– Cut grass before it goes to seed. Fresh ‘green’ clippings will add nitrogen to the soil, which helps plants grow. If you let the clippings turn brown, you will get the mulch effect without adding nitrogen.
- Yard waste– Cut up any branches or woody material.
- Compost– Needs to be ‘finished’ compost so as not to attract pests.
- Hay– Good mulching material but beware – weed seeds may be introduced.
- Straw– Good source of carbon; excellent mulching material.
- Fine bark– Can be acidic. You may need to add lime at the same time.
- Wood Shavings– Avoid shavings from chain saws or tools that leave oil residues.
- Leaves– A valuable source of carbon, leaves make excellent mulch. Apply in thin layers, or intersperse with other materials to prevent matting.
- Forest duff– Pine needles, twigs, woody bits are useful, but can be acidic.
Creating a No-Dig Garden / bed / pot
Step 1 – Prepare the Soil
Step 2 – Lay down Manure & Compost
Keep the materials away from the stems/trunks of existing plants to avoid ‘collar rot’ – rotting the base of the plant. Worm castings or rock dust can also be added into this layer.
Step 3 – Lay down Mulch
Any carbon containing material such as peas, straw, hay, sugar cane mulch, alfalfa, leaves, grass clippings, seaweed, wet strips of newspaper, coarse sawdust or bark mulch etc can be used.
No-Dig Garden Maintenance
After the plants are harvested and the growing season has ended, the layers will have rotted down into the soil, enriching and improving it. It’s then time to replenish the no-dig layers
To replenish the layers of the no-dig garden at the end of every season:
- Add a layer of manure as before (and compost if you wish, which is optional),
- Cover the manure/compost layer with a layer of straw
- Water it in
Cut back on watering :The use of mulch retains moisture, thereby reducing the need for frequent watering. Reduced watering also helps minimize soil compaction and the germination of unwanted weeds.
Avoid compacting the soil :Do not step on the soil as this compacts the soil.
Soil for the Pots :Following the no dig or layer gardening way, you can either:
- Build up the soil in the pot using no dig materials, making layers such as hay, fertilizer, straw, compost etc, then topped with mulch.
- Make compost actually in each pot, adding enough soil layers to supply some worms and bugs to help turn it all into compost.
- Use very large spare containers with lids as mini compost bins to do as above and then use the composted or nearly composted soil to fill up your pots as you need to. This can be done using kitchen scrap and some soil.
The pot can be made with
- 5 cm layer of rubble – only required on poorly drained soils
- 5 cm layer of overlapping newspaper (don’t use glossy paper or cardboard)
- Layer of mulch, for example: alfalfa, leaves, grass clippings, seaweed, wet strips of newspaper, coarse sawdust or bark mulch.
- Sprinkling of 2 to 3 cm layer of well-rotted animal manure
- 2 cm layer of loose straw
- 1 to 2 cm deep layer of compost (or a mix of compost or planting mix).
No-dig gardening, not only reduces effort and time spent in the garden but also saves energy and water, maintains a healthy soil ecology, and lets Nature do the work. It’s the way Nature does it, and it’s the most sustainable way you can garden!