This is a system of gardening in which organic products (derived from organisms which have had life) are used to maintain and increase soil fertility. Until the nineteenth century gardeners relied almost solely on organic wastes for manuring the garden soil. Animal dung was extensively used in Europe. The art of mixing animal and vegetable wastes together and the fermentation of the mixture in heaps developed in various parts of the world—notably in China.
Justus von Liebig, the German chemist and discoverer of chloroform (1803-1873), suggested that plants might feed on chemical compounds and the world-wide application of factory-made chemical plant foods to farm and garden soils has resulted from von Liebig’s correct hypothesis. Between 1840 and 1940 the use of chemical fertilizers, known as `artificials’, became an almost unquestioned garden practice. The belief was current that to obtain maximum yields it was necessary but to lime, where lime was needed, and to fertilize the soil with appropriate quantities each season of suitable chemicals containing nitrogen (N), phosphorus (P) and potassium (K).
The German philosopher, Dr Rudolf Steiner (1861-1925), questioned the wisdom of the NPK theory and originated the bio-dynamic method of organic gardening. At around the same time Sir Albert Howard (1873-1947) was experimenting in India in an attempt to produce a cheap manure for use by the Indian farmer. It was in India that Sir Albert perfected his Indore (not indoor) way of composting animal and vegetable wastes. Applications of Indore compost not only led to excellent crops but important side-effects were observed. Food plants growing in Indore-composted soil showed unexpected, healthy vigor. Cattle fed on the healthy crops became robust and, like the plants, they showed resistance to some diseases. Sir Albert Howard’s book, An Agricultural Testament, was hardly noticed by leading horticulturists of the day. The book has since revolutionized the horticultural scene. Knowledgeable gardeners now accept as an axiom that garden compost replaces horse dung and farmyard manure as a source of plant foods and as a soil improver. Not all gardeners reject the NPK theory entirely. Those who do are known as organic gardeners. They seldom, if ever, use `artificials’ claiming that they have no need to buy factory products when by the use of garden compost first-class crops are obtained.
The organic gardener expects his growing plants to have the robust health, noted by Sir Albert Howard during his experimental work, and has no use in his garden for chemical sprays and powders for controlling plant pests and diseases. The practice of organic gardening presupposes that the gardener has some knowledge of horticulture. Exponents of this ancient method, combining a modern approach, rightly insist that no gardening technique, however good, can lead to optimum results unless basic horticultural principles are understood. They also add that it is impossible to state accurately how quickly a garden soil may be renovated and brought to a high state of fertility by organic methods. Much depends on the soil type, on its condition when the experiment begins and also on the amount of suitable organic matter added. During the transition period it may be necessary to buy and use some chemical products; this is the view of an author of a standard work on organic gardening.
In the view of defenders of organic gardening the NPK era was an erroneous, short, but extremely dangerous period in mankind’s history.
Organizations based on the work of Dr Steiner and Sir Albert Howard exist in many countries. Their vociferous demand that waste materials should not be dissipated but used to improve and maintain soil fertility is heeded in most parts of the world. The relationship between unadulterated food and good health, prevention of soil and water pollution, prevention of soil erosion and the conservation of many natural resources are among the subjects which concern such organizations. This is in addition to their primary interest in the production of healthy, health-giving food crops from the farm and garden. Cities as far apart as Edinburgh, Tel Aviv, Bangkok and Moscow now make and supply municipal compost from town wastes.