Organic farms are inspected and certified by the Soil Association, or one of ten other certifying bodies licensed by the government. Farmers who want to go organic need to show that organic and non-organic units or operations on their site are separate, and that they can trace all materials back to their origins. The process of certification takes about 12 weeks, but the minimum time taken to convert a farm to organic is around two years. Organic farms are re-inspected yearly and are also subject to unscheduled spot checks. Farmers have to keep records showing that they are meeting organic standards.
Organic farmers aim to keep their farming systems in balance with nature, rather than depending on synthetic herbicides and pesticides. They control pests, disease and weeds by methods such as mixed/companion planting, manual weeding and pest control, physical barriers, and by using products such as lime, seaweed and farmyard manure to increase soil fertility. Organic farming also promotes biodiversity; for example toads and hedgehogs are encouraged as they are natural predators of slugs. As a very last resort, for example if a whole crop is threatened, organic farmers are allowed to use a limited number of naturally-sourced pesticides that are non-toxic to people and wildlife. Before doing this, they have to be given permission by the certifying body.