Attractive showers of powder-blue flowers smother mounds of foliage all summer continuing into autumn, creating a long lasting border display from this outstanding perennial.

Height: 45-60cm (18-24in) first year up to 90cm (3ft) in second year.

Sow January - April. Sow seed on the surface of lightly firmed, moist seed compost in pots or trays. Cover seed with a very fine sprinkling of compost or vermiculite. Keep at a temperature of between 21-29C (70-85F). After sowing, do not exclude light as this helps germination. Keep the surface of the compost moist but not waterlogged; germination will usually take 7-21 days.

When large enough to handle, transplant seedlings into 7.5cm (3in) pots or trays. Gradually acclimatise plants to cooler conditions for a few weeks before planting out after all risk of frost, 30-45 cm (12-18in) apart.

For the best results, plant in a sunny or lightly shaded border in ordinary well-drained garden soil.