Sales of organic goods in the UK grew to around £1.6 billion last year - an annual increase of 30%, or an extra £7 million a week. The range of consumers buying organic has also broadened, with the goods no longer the preserve of the affluent.

Helen Browning from the Soil Association said:

"These are staggering growth figures and clearly good news for UK organic producers.

"It is also greatly encouraging to see supermarkets responding to criticisms by increasing their sourcing of home-grown produce."

But the Soil Association, which certifies organic producers, is concerned that demand will outstrip supply in the UK.