One More Dahlia (gouache style)

Dahlias are tuberous perennials from the mountains of Mexico and Central America, and the dahlia is Mexico's national flower. The plant was named after Anders Dahl, an eighteenth-century Swedish botanist. Gardeners sort dahlias into groups by flower shape, from tight pompons and spiky cactus types to open singles and big decoratives. Singles and other open-centred forms are the ones bees can actually use, since fully double blooms hide their pollen.

Because they're tender, dahlias can't go outside until the risk of frost has passed, usually late May or early June. You can start tubers in pots under cover in March or April to get ahead. Put in a stake at planting time, protect young shoots from slugs, and water and feed well through summer. Cut or deadhead regularly from July. When the first frost blackens the leaves, lift the tubers, dry them and store them frost-free, or in milder areas leave them in the ground under a thick mulch.

Here the flowers are coral and pink, with chartreuse foliage set against a pale lilac ground. They're bold colours for a bold plant, and the leaves play as big a part as the petals. The title nods to the habit every dahlia grower gets into: cutting a stem for the house, then going back out for one more.