Under the agreement, which sees the two brands working together for the first time, 40g packs of Ocean Spray Craisins - sweetened dried cranberries - will be given away free with Florette's crispy and mixed salad bags.
The campaign runs for four weeks from 9 March and aims to encourage consumers to try on-pack recipes that combine Craisins and salad.
Consumers were looking for new tastes and flavours as they stayed in to dine rather than eating out, said marketing manager at Florette, Elaine Smith.
Packs will also include a 20p money-off coupon for shoppers to use against a future purchase of Craisins. "The joint activity will help us inject impact and personality to the bagged lettuce aisle," said Smith.