BBC Gardeners' World

Plant details

• Common Name: Granny's bonnet
• Genus: Aquilegia
• Species: vulgaris var. stellata
• Cultivar: 'Black Barlow'
• Skill Level: beginner
• Exposure: full sun, partial shade
• Hardiness: hardy
• Soil type: chalky/alkaline, clay/heavy, moist, well-drained/light
• Height: 0.76m
• Spread: 0.45m

Popular for its late spring and early summer dark plum-purple flowers, it makes a stronger show than the more well-known 'Nora Barlow' which has much paler, pinker colours. 'Black Barlow' makes an effective contrast with white alliums and white sweet rocket, and other aquilegias such as the purple and white 'Colorado' and the red and gold 'Kansas'. It likes moist but free-draining soil where it will self-seed prolifically. You can either collect the ripe black seed in the early autumn and sow it in pots in cold frames, or gently move the young self-sown plants in the garden to more favourable positions in the spring. It's possible to divide cultivars in the spring, but they sulk for quite a while until they have fully recovered.