The Git has been developing a system of gardening based on selected aspects of the French-Intensive and Biodynamic gardening (Biointensive) methods for 33 years. His garden consists of raised beds 1 metre (39″)wide and 8 metres (26′) long. The soil is heavily composted, about 25 mm (1″) being added per year. The high level of fertility engendered allows much closer planting than is usual, without sacrificing yield per plant. The high humus levels also reduce watering needs, due to water retention by the organic matter. As the beds are raised about 100–150 mm (4–6″), drainage Is never a problem.
The footpaths between the beds are 450 mm (18″) wide and allow cultivation and weeding to take place without walking on the beds. Much of the cultivation required in conventional gardening and farming is repairing damage due to soil compaction caused by trampling the soil between the rows of plants. In The Git’s garden, plants are grown in closely spaced blocks rather than rows. While this noticeably increases the yield per unit area of large plants, such as brassicas, the yields of many crops, carrots, potatoes and lettuce for example, are dramatically greater.
Originally, the beds were free-form. The footpaths were kept clean with a GR wheel-hoe purchased from Gundaroo Tiller. Over the years, The Git has experimented with various ways of treating the footpaths, and in his retirement uses the following strategy. The free-form beds suffered from “bird erosion” as the blackbirds moved soil from the edges of the beds into the footpaths while seeking earthworms. Placing 150 mm wide boards down the edges of the beds has reduced this erosion considerably and a significant gain in yields of closely planted vegetables such as carrots since the plants near the edge are no longer uprooted. The footpaths are mulched first with plastic weed-mat and then covered with a thick layer of sawdust as that is available for the cost of transport locally. Cardboard instead of plastic weed-mat is attractive from the point of view of recycling waste material, but has two distinct disadvantages. It decomposes quickly and in wet weather, is treacherously slippery underfoot.
The increase in yield per unit area reduces the amount of time required for many garden operations, such as cultivating, weeding, watering and composting, since a smaller garden is required to satisfy a family’s needs. The advantages of the system are so great that many commercial vegetable growers have adapted it to a mechanised system. The tractor tyres are confined to running in the between bed ‘footpaths’ and the grower benefits from the reduced amount of expensive cultivation, as well as the higher yields. The downside for the commercial grower is the lack of purpose-built equipment using the same spacing between wheels even 30 years after tram-tracking as it is called was introduced. It still requires customising seeders, harvesters and cultivators, by no means a trivial thing to do with expensive machinery.
Since the garden becomes divided into clearly defined areas, planning rotations and crop requirements is greatly simplified. As an example, a temperate climate family might require an average of two carrots a day from early summer to early spring. The superb drainage of the raised beds enables the carrots to be harvested as needed, rather than lifted and stored. Two carrots per day for ten months is about 600 carrots. Each carrot requires about 60 square centimetres (9 square inches) of growing space, so a 1.2 metre (4 ‘) wide bed would need to be 3 metres (10’) long to accommodate this need. As the carrots are dug, the soil is raked smooth, compost applied and whatever suits the planned rotation of the gardener sown or planted out.
Carrots at thinning
Carrots halfway to maturity
No weeding needed here!
In a temperate climate, a 130 square metre (1400 square feet) garden (including paths between beds), is sufficient to grow the needs of a family of four in a six month growing season. In a harsher climate, a garden twice this size might be needed. Advantage is taken of the wide spaces between slow growing crops, such as cauliflowers, to grow quick maturing crops, such as lettuce and radish.
The method, as originally published by John Jeavons, requires double-digging. That is, the soil below spade depth is broken up with a garden fork. This extra labour may not be necessary , especially where deep frosts are prevalent. Unless the subsoil is particularly compacted, digging to a spade’s depth should be all that is necessary , and that only once during the creation of the raised beds. The Git uses a long-handled fork thrust deep into the soil and levered back and forth once every year or two. Mostly, he just tills the top 100 mm (4″) with a four-tined cultivator. Deep-rooting crops and a multitude of earthworms do much of the soil aeration required for plant health. Vegetables grow best in soil that consists of ~50% air, ~10% humus and other organic matter, and ~40% minerals (sand, silt and clay).
Tillage with the cultivator takes place when the bed is composted prior to the planting of a crop. This occurs as long as possible before the crop is sown, or planted out. When weeds are at the white-wire stage, a quick going over with the rake is all that is needed to kill the weeds. Widely spaced crops, such as brassicas, are weeded with a gung-hoe. The advantage of Eliot Coleman‘s design is that it minimises the effort required to use it. Conventional hoes use the wrist muscles, the Coleman design uses the shoulder muscles which fatigue much slower. Close-planted crops such as carrots are weeded with fingers. Provided the bed is already relatively weed-free, this occurs at the thinning stage and adds little to the time required. As the plants’ foliage merges with adjacent plants, the soil is shaded and subsequent weed growth is negligible. The dense foliage protects the ground from compaction and erosion by rain and irrigation, as well as shading the soil thus reducing moisture loss. Sort of like a miniature rain forest.
Throughout the year, The Git uses a very dilute mixture of fish and seaweed emulsion both as a foliar amendment and a soil drench. For soil drenching, molasses is added at the rate of about a table-spoonful per 4.5 litres. This assists the breakdown of cellulose in crop residues. During the spring, summer and autumn, the foliar spray is applied every two weeks; monthly in the colder months.
This is intensive agriculture, something the Greens apparently abhor. Supposedly, intensive agriculture requires huge inputs of artificial fertilisers and synthetic pesticides. The method described above produces 4–6 times the yield of agriculture based artificial fertiliser and uses none of the synthetic pesticides. According to Jeavons, it uses 1/4 of the land, 1/3 of the water and 1/100 of the energy per unit weight of food. The Git believes that these numbers are within the ball-park.
The persistent myth of lower yields from organic methods comes from comparing conventional row culture using artificial fertiliser and synthetic pesticides to the same row culture minus the artificial fertiliser and synthetic pesticides, the so-called “do nothing” method. While the Biointensive method reduces pest and disease problems to a minimal level, using artificial fertiliser, or nothing has the opposite effect, but more on this later.
Brassics showing collar that protects against slug & cutworm damage early on
The collar, made from off-cuts of uPVC pipe also concentrates soil drenching with dilute fish and seaweed emulsion at transplanting time where it’s needed.
Spuds in foreground, broad beans behind
The broad beans were harvested in late December, four weeks later than usual.
Peas, the ones on the right have “shrunk” under the weight of the crop
French beans showing the effect of “global warming” (AKA cold).
This picture was taken in the height of summer (February). Daytime temperatures have been between 11°C and 15°C for many days at a time.
Next time The Git will discuss some of the science behind organic production systems versus conventional.