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: tolerant of most, but prefers moist but well drained, humus rich soil
• Rate of growth: fast
• Flowering period: July to September
• Hardiness: fully hardy
  
  Ideal for the larger wildflower garden, or for establishing new borders, this very pretty, summer flowering perennial is much more garden-worthy than the species. It spreads to form sizeable clumps relatively quickly, and from midsummer is crowned with tapering spires of white flowers. It's very impressive when in full bloom - particularly when used to illuminate an area of partial shade.
  
  
• Garden care: Easy to grow and undemanding, they should be deadheaded to prolong flowering, and cut down to just above ground level in autumn. Over-large clumps can be divided in spring or autumn.