The announcement coincided with the Queen planting trees at the new 8ha Jubilee Wood at Sandringham, Norfolk, on 6 February to mark 60 years exactly since her accession to the throne.
Over the next 15 months Sainsbury's will raise £1.5m for tree planting by increasing the number of donations made from products in store. The supermarket already donates money from the sale of eggs, chickens and turkeys to the Woodland Trust.
Sainsbury's chief executive Justin King said: "We have ambitious plans to plant twomillion trees by 2015. This project is integral to this commitment."
The Woodland Trust is twinning the project with one to create a Sainsbury's Wood in its flagship Diamond Wood in Leicestershire, said chief executive Sue Holden.