Making Better Soil in your Vegetable Garden

There is a great deal of interest in regenerating soils and in regenerative agriculture. Regenerative agriculture is about applying ecological principles to food production; taking care of the natural resource, and valuing biodiversity. It is a conservation and rehabilitation approach to farming systems that mimics natural biodiverse ecosystems and natural processes. But, within this approach we have to keep in mind is that there is no one size fits all.

Farming regeneratively and regenerating soils as a grazier is different to how a grain farmer will farm regeneratively, likewise, for those of us who are small market gardeners.  How we practice regenerative horticultural will take different pathways than the grazier, the grain farmer, or the viticulturist. However, the broad principles are the same no matter what you are farming. Each one of us in our different farming endeavours has to consider how we adapt our farming system to mimic ecosystems and how we apply ecological principles in our landscape.  

So, what does this mean for the market gardener?  To regenerate soils, we have to look at what we plant and add to the soil; how we plant, and how we adapt this process.

We already know as organic practitioners, the value of compost, organic matter, crop rotation and cover cropping, and have some understanding of soil structure, soil fertility and soil nutrient exchange.  We also have some recognition of the importance of microbial activity.  In reality it is only in the 20th century that we have embraced practices that ignore our environment, biodiversity and soils.  We are fortunate that we can access both past knowledge and practices and new knowledge, incorporating all.

First, some old knowledge. Organic systems of intensive horticulture have been practised for thousand years (at least 4,000 years ago in China, 2000 years in Greece, and at least 1000 years ago in Latin America.)  In more modern times these horticulture practices were re-developed in Europe during the 1700s through to the early 1900s. Most notably the French intensive techniques developed by market gardeners outside Paris. The crops were grown so close to each other that when the plants were mature, they created a mini-climate and a living mulch that reduced weed growth and helped hold moisture in the soil.

In 1924, in Germany, Rudolf Steiner delivered a series of 8 lectures on Agriculture in response to a request by farmers who noticed degraded soil conditions and a deterioration in the health and quality of crops and livestock resulting from the use of chemical fertilizers.  These lectures became the basis for Biodynamic agriculture with an emphasis on the use of manures and composts; soil fertility, plant growth, and livestock care as ecologically interrelated tasks.

The Grow Biointensive method as initially developed by Alan Chadwick in (1966) and practised and promoted by John Jeavons through Ecology Action (from 1970) is a combination of two forms of horticulture – French Intensive methods and Rudolf Steiner’s Biodynamic Agriculture and more recently from permaculture we further know the value of polycultures.

Most small market gardeners through the work of Jean-Martin Fortier (The Market Gardener) And Eliot Coleman (The New Organic Grower), understand the key concepts of intensive polyculture:

• Building soil
• The use of compost (humus) for soil fertility and nutrients
• Close plant spacing – Maximising the effectiveness of time and space.
• A whole, interrelated farming system.
• Inter-planting or Poly-culture planting.

It is the aspect of inter-planting or polyculture planting where I think the small market gardener can continue to improve in relation to how we plant and what we plant for soil regeneration. There is still much to learn about the important role polycultures play in building soil microbiology.

Currently intensive polyculture is most commonly interpreted as growing 4 to 6 rows of the one vegetable in the one bed, adjacent to another bed of 4 to 6 rows of a different vegetable, and so on.   This is not inter-planting and is not the best form of poly-culture planting

Specifically, inter-planting means growing two or more types of vegetables in the same place at the same time.  In all the reading that I have done over the years this concept is only fully explored through the work of Ecology Action & John Jeavons (How to Grow More Vegetables than you ever thought possible…) and Linda Woodrow (The Permaculture Home Garden) .

Both these horticultural writers take the concepts of interplanting and polyculture planting to a completely different level.  At Wynlen House we have adapted the principles of bio intensive polyculture from their work to develop a species specific planting for all season growing in very cold regions.

The bed below is an example of inter-planting: A row of broccoli with lettuces planted in between the broccoli down the row; and an example of a poly-culture bed planting as used in our horticultural practice.

Bed – 20m long X 80cm wide

This is creating a ploy-culture in a bed or in permaculture terms a guild, a carefully constructed assembly of species that each contribute to the synergy of the whole. We have been practicing this type of poly-culture planting and inter-planting for over 10 years with great success.

You may also be aware of the research that has shown when 5 specific family species are planted together (grasses, cereals, brassicas, chenopods and legumes) there is a synergy created.  We are now incorporating an under sowing of a green manure, a mix of grasses, cereals, and legumes (the beds already have brassica and chenopods) to create synergy and enhance microbial development.

See bed example below. In this example, we are using a number of different principles (as well as companion planting) to select the vegetables to be planted together. We outline this in detail in Wynlen House’s Bio Intensive Polyculture online and on-classes.

Bed – 20m long X 80cm wide

We anticipate that incorporating a green manure crop into our planted bed in this way will provide the general benefits that green manures bestow – inexpensive nitrogen, organic matter, nutrient building etc;  It will also see the green manure well established and ready to be turned in by the time the bed is fully harvested.  In the peak spring and summer growing period, in the cold climate market garden, when time is short, the under-sowing of green manures will provide the benefits without taking beds out of production.

We will keep you posted.