Sorrel leaves are used extensively in French cuisine, in fish, soups and sauces, also picked young will add a tart flavour to a mixed leaf salad. Sorrel leaves are best harvested regularly whilst small as bitterness increases with larger, older leaves.Sow seeds March to May, fortnightly for ‘salad leaves’. Sow seeds thinly, 12mm (½in) deep in drills 30cm (12in) apart.Thin seedlings if necessary, when large enough to handle, to 15cm (6in) apart. Keep ground weed free and water well during dry periods. Harvest 6-8 weeks after sowing, selecting a few leaves from each plant.Harvest regularly from early summer to frosts.