Information on Purple-loosestrife

Common Name: Purple-loosestrife
Scientific Name: Lythrum salicaria
Irish Name: Créachtach
Family Group: Lythraceae
Distribution: View Map (Courtesy of the BSBI)
Flowering Period


Click for list of all flowering by month
Purple-loosestrife is not easily confused with other wild plants on this web site.


This beautiful, upright perennial of ditches, river banks, canals and marshes is a much loved sight from June to September throughout Ireland.  Its flowers are borne in dense whorls on upright spikes, each flower 10-15mm, bright reddish purple, with six crumpled, narrow petals and twelve stamens.  However sometimes there can be fewer petals, different sized stamens and styles. The paired , opposite, lanceolate leaves are in whorls of three but those further up the stems are sometimes alternate.  This is a native plant belonging to the family Lythraceae.  

I first identified this plant in 1973 at Salerno, Co Galway and I photographed it in Tullycanna, Co Wexford in 2006. 

If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre

Purple-loosestrife
Purple-loosestrife

'When on the water op'd the lily buds,
And fine long purples shadow'd in the lake,
When purple bugles peeped in the woods
'Neath darkest shades that boughs and leaves could make.
'

      John Clare   (1793-1864)