Iain Tolhurst has been a certified organic grower for more than 30 years and is a pioneer in organic stockfree techniques. The green manures which he uses are Lucerne and clovers. The tap root of the Lucerne goes deep into the soil and breaks it up, releasing nutrients.
Tolhurst uses a rotation system of 7 years:
Years 1 and 2: Green manures.
Year 3: Potatoes.
Year 4: Brassicas.
Year 5: Alliums – onions, leeks, etc. Planting these after the brassicas helps to inhibit the diseases which the allium family are prone to.
Year 6: Root vegetables – parsnips, celeriac, beetroot, carrot. These can grow at lower levels of soil fertility.
Year 7: Squash and sweetcorn.
Weed control is helped by rotation. Some hand weeding is necessary from time to time but is kept to a minimum.
The brassicas (cabbages, sprouts, etc.) on Tolhurst’s plot are clearly unaffected by pests. He explains that this is due to the fact that there are parasitic wasps on the site which are natural predators of the caterpillar and cabbage white butterfly. Tolhurst says they have almost zero damage from caterpillars. This is also due to the fact that the predators are encouraged all year round – they can migrate to beetle banks and hedges nearby, and there is always a crop of brassicas to encourage them all year round. He says that this method is very effective and far superior and less time consuming than methods which use sprays and pesticides.
Artichokes are used as a wind breaker, to increase biodiversity and to encourage insects and small mammals to take up residence. Flowers and nettles form part of the hedge areas as they attract beneficial insects. Berry plants attract birds which in turn control the insect population.
Tolhurst believes that stockfree organic is the way forward. His produce is distributed to customers via a box scheme and he says that they are active 51 weeks out of every year. His website is: http://www.tolhurstorganic.co.uk/