Botanical Iris (botanical style)

The iris takes its name from the Greek goddess of the rainbow, a nod to its range of colours. Each flower has three upright petals called standards and three drooping ones called falls. On a bearded iris, each fall carries a fuzzy line of hairs, the beard, which guides bees towards the nectar. It's an old heraldic flower, the model for the fleur-de-lis, and the dried rhizome of some species, sold as orris root, is used in perfume.

Bearded irises flower in May and June and want full sun and sharp drainage. Plant the rhizomes between July and September, with the top half left above the soil so it can bake in summer. Don't bury them or smother them with mulch, as they rot easily. Every three to five years, after flowering, lift crowded clumps, throw away the old woody centre and replant the younger pieces, trimming their leaves into a short fan so wind won't rock them loose.

A purple bearded iris is drawn here complete with its rhizome and leaves, on a cream ground. The rhizome normally sits half hidden at soil level, so including it shows how the plant grows and spreads. Standards, falls and the sword-shaped leaves are all in view, the parts a gardener learns to recognise first.