Little Gem is so widely regarded it is sold by that name in the shops and has become a generic term for this type of small-hearted cos lettuce. Few match the flavour and texture of this much-loved and widely grown original. One of the best lettuces you are likely to grow, it has the Royal Horticultural’s Award of Garden Merit. Lettuces do best of all in fairly light, fertile, well-drained soil, especially when well-rotted organic matter has been added to improve moisture retention. An open, sunny site is best. They will not thrive on poor soils which dry out during summer.