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The single most important thing that a grower can do to be successful is to have healthy, nutrient rich soil.

In nature, leaves and plants fall into the ground and decay, animals eat plants and return manure to the soil, and the bodies of dead animals decompose. Soil is the combination of decaying vegetation and animal matter, manure, and weathered rock.

One tablespoon of soil holds more than six million micro-organisms. These organisms interact with organic and inorganic materials to breakdown nutrients and make them available to plants.

Soil forms at a rate of 1mm every one hundred years. Since 1945 the amount of productive soil per person globally has decreased by one third due to erosion caused by overgrazing., deforestation, use of chemical fertilisers and mechanized farming methods.

Maintaining good soil
After harvesting, growers need to replenish what they have taken away or the productive topsoil layer becomes depleted.

The best way to do this is through the use of compost. Compost helps create a good soil structure that is better at retaining water, and feeds the soil micro-organisms. Organic growers must get their compost ingredients approved by a certifying agency, or buy it from approved suppliers. Sewage is not a permitted ingredient.

But organic growers do use fertilisers, as compost alone is sometimes not sufficient to help quick growth (necessary for tenderness in some fresh vegetables), or to get the best yield possible. These natural fertilisers include limestone, sea salt, seaweed and approved fish products, as well as plant and herbal extracts. Chemical fertilisers can actually make conventionally grown plants mature too quickly, creating a thin cell structure in the plant. This "thinness" results in the plant breaking down very quickly after harvest which means a decreased storage time on the shelf or in your fridge. Organically grown crops are not affected to the same extent.

Another way to maintain soil fertility is by planting cover crops. Cover crops such as buckwheat, lupin, alfalfa and clover are grown to improve soil fertility and to protect the soil from erosion of wind and water when crops are not being grown. When cover crops are turned under, the decaying matter helps build up topsoil. They also supress weeds, and prevent soil from crusting during long , hot summers.