Sainsbury's has told all its fresh produce growers in the UK to adopt new wildlife-boosting conservation measures.

As part of Operation Bumblebee, farmers have been asked to sow wild flowers on field margins to encourage bees, insects and small mammals to return.

Sainsbury's is rolling out the initiative, set up by biotech giant Syngenta five years ago, to all 300 of its British growers.

"This is a good way of showing that we care for the environment by moving away from intensive farming," said a spokeswoman.

"Almost all of our core vegetables are grown in compliance with this scheme, including carrots, cabbages and onions. We expect to have all our home-grown spuds, veg and some fruit in line by this time next year."

The next step is to look

at how to brand Bumblebee and present it to consumers. Sainsbury's wants to use it as a point of difference in the fresh produce aisle, and in the process, take on the likes of Waitrose, which has long made a virtue out of its environmental policies.

The scheme has been welcomed by growers,

even though it entails a small extra cost as they can no longer grow crops on field margins and must carefully manage the wild flowers to prevent them being choked by weeds. Sainsbury's provides some training.

But watercress grower Vitacress has already been running the scheme for years and said that it was worth it.

"It has commercial benefit as a natural barrier to pests, especially now farmers are allowed to use fewer pesticides," said Simon Conway, Vitacress commercial manager.

"Waitrose is good at selling what it does with farmers but Sainsbury's move has a much bigger impact because it is on a larger scale."