Soil Organic Matter – No Till or No Dig Gardens
New Approach to an old problem
No till farming is attracting increased interest from farmers around the globe.
Those who have adopted this move have lifted their’ bottom line’ balance sheets mainly through lower input costs on such items as:
- Chemicals and
- Machinery costs
Because crop yields have remained very similar overall farm profits have increased.
Reasons behind this change revolve around the adoption of 3 key practices:
1. Little or no tillage of the soil
2. Use of cover crops
3. Use of complex rotations
A move toward the adoption of these practices has seen large increases in soil organic matter with associated benefits such as reduction in irrigation through better soil water holding capacity and formation of good soil aggregates and more importantly an increase in microbial biomass- this has been referred to as the ‘Invisible Herd’ or ‘Underground Economy’.
As a gardener I have considered the idea why can’t we adopt these same practices in the home garden.
The key leaning point is ‘Keep the soil of ground in cover’- as the roots of any crop are what fuels the soil engine.
We can do this by:
- Reducing tillage
- Using cover crop when required and use a mix of up to 6 different tillage crop types and
- Crop Rotations
Gardeners including myself have tended to winter fallow and have bare soil so that in effect there is no carbon building in the soil and more importantly little biological activity due to their being no plant roots available to fuel microbial activity.
In my view we can start with planting a cover crop in autumn using a mix of cereal grass, broadleaf plants and legumes.
After these are well established,
- Cut down in late winter leave on the soil surface so as to form a mulch or soil cover
- Spray over this with an application of liquid fish fertiliser [this is rich in fatty acids and will help deter fungal pathogens whilst also supporting beneficial organisms and micro flora.
In early spring you can aerate your soil thru the cover using a long tined fork – broad fork is the ideal and then soon after plant your first crops by pulling back the mulch and planting into the soil below = The photo shows sweet corn seedlings planted into a pea straw mulch. The corn was planted in early November 2018 and certainly helped the soil retain moisture during what turned out to be a dry season and irrigation was less than I would normally have expected.
Another option is after cutting down the cover crop apply compost over the top plus apply any soil amendments that you may require. Personally I like using seaweed powder, guano and lime, if needed.