RHS good plant guide.

This pocket-sized plant guide lists over 3000 plants that have received the Society's Award of Garden Merit, given only to outstanding plants that are deemed to be excellent for garden use, that are easy to grow, reliably healthy and with outstanding ornamental or productive qualities. There is a quick reference listing which recommends a range of plants for every situation: plants for problem sites, quick container solutions, the best in summer bedding and high performance fruit and vegetable varieties.