In the 20th century, industrial farming brought chemical fertilisers, tractors and combine harvesters. Short term yields increased, whilst effects on soil fertility, plant vitality, plant nutrients etc took a back seat. At least in the mainstream….
The 20th century also saw the emergence or re-emergence of other approaches. Four of those are discussed here.
ORGANIC agriculture was based around only using naturally derived inputs to fertilise soil, notably the use of compost, the use of green manure crops to fix nitrogen in the soil, the development of plant and herbal teas to feed to crops, the use of open-pollinated seeds, the provision of sources of nectar for pollinators and plants to divert pests away from crops. Albert Howard, the Henry Doubleday Association and the Soil Association were all prominent in that effort.
NO-DIG agriculture may or may not be organic (although I believe most if not all of its practitioners are organic adherents) but focuses on leaving soil undisturbed throughout the year, letting earthworms, fungi and bacteria develop a rich topsoil, good drainage and healthy pH for the soil. A Guest of Yorkshire, Ruth Stout in the USA and Charles Dowding in Somerset have all contributed significantly to its development.
BIODYNAMIC Agriculture emerged from the teachings of Rudolf Steiner in Austria in the early 20th century, focussing on running a farm as a single holistic organism. The use of particular sprays and preparations, notably horn manure and horn silica is reputed to improve soil fertility, improve nutrient uptake and assimilation by plants (notably silica) and improve resilience to pests and disease. More recently, Maria Thun has suggested that outcomes may be improved by perform key activities at certain times of the lunar cycle. Furthermore, preparation of compost piles using the biodynamic preparations is said to enhance compost quality, perhaps through optimising heap temperatures (and the bacterial composition within them) during maturation.
PERMACULTURE as a term emerged from the work of Bill Mollison in Tasmania, who coined it as an acronym for PERMAnent agriCULTURE. It focusses on sustainability, particularly within warmer and drier regions, but can be applied in a locally adpted manner anywhere in the world. It focusses on water retention, collection and recycling; polycultural planting; the use of perennial plants to create forest gardens; the use of animals to clear and fertilise areas prior to planting (chicken and pig tractors) etc.
What all the four approaches agree on is that CARE OF THE SOIL is paramount. All agree on the recycling of organic waste into soil, be that through composting, mulching and/or application of organic teas.
Differences may be due to different desired outcomes. If you are a vegetarian market gardener, you may not keep chickens to clear ground for no-dig beds, preferring to apply a mulch of manure instead.
Similarly, if you do not have 60 hectares for biodynamic rearing of animals in general and cows in particular, you may not acquire cow horns and healthy manure to use in preparing horn manure, choosing to buy small quantities instead commercially.
Those seeking to convert impermeable clay to deep fertile topsoil may consider initial growth of deep rooting green manures such as alfalfa or crimson clover to break open the soil, the generation of hay for composting etc. Clay may after all be the result of previous forests dominated by fungal soils, rather than those with more bacteria suited to vegetable growing by market gardeners. But those growers are seeking to improve soil fertility for their own aims.
Biodynamic growers believe in composting in autumn, just like organic gardeners and no-dig adherents. They believe the horn manure spray after composting enhances the over wintering maturation ready for sowing in spring. They happen also to believe that the soil is preferentially responsive on certain days during the lunar cycle.
Permaculturists are perhaps the most laissez faire of all, after being master planning apparatchiks at the start. A permaculturist moulds the landscape to their desire, plants an ecosystem to create a sustainable ecology, then sits back and admires their work, occasionally harvesting crops like an old fashioned hunter gatherer.
There is little reason for these four disciplines to be anything other than cooperative. Different folks will feel more at home with each approach, but all seek to care for the soil.
There is indeed an argument that all should join forces under a framework of Innovative Ecology, Soil Science and Agriculture (of which Horticulture is a valued part). What the banner should be is a secondary consideration, since without cooperation and unity no banner would exist.
All four approaches have educated my path toward gardening sustainably, they all have their part to play in restoring health to the world’s land surfaces.