Lythrum virgatum, or Loosestrife is a fast growing large perennial with huge heads of purple flowers, borne on upright stems growing to 1.2m. 

This loosestrife variety is not native to the UK but is still beneficial for pollinators. Plant along marginals or pond edges in boggy soil as it likes to be in permanently moist conditions. Provides a spectical of colour throughout summer. Also suitable for a reliably wet area of the garden and works well with other lythrums.