This perennial dies back to below ground level each year in autumn, then fresh new growth appears again in spring.

• Position: full sun or partial shade
• Soil: moderately fertile, moist, well-drained soil
• Rate of growth: average
• Flowering period: July to August
• Hardiness: fully hardy
  
  Upright, leafy stems are topped with candelabra-like racemes of lilac-blue flowers from midsummer. Tall and elegant plants, which are valuable for adding colour and interest towards the back of the border, their silhouette will remain interesting well into winter.
  
  
• Garden care: Divide plants in spring. Apply a generous 5-7cm mulch of well-rotted garden compost or manure around the base of the plant in spring.