Information on Giant-rhubarb

Common Name: Giant-rhubarb
Scientific Name: Gunnera tinctoria
Irish Name: Gunnaire
Family Group: Gunneraceae
Distribution: View Map (Courtesy of the BSBI)
Flowering Period

Click for list of all flowering by month
Giant-rhubarb could sometimes be confused with:

Giant-rhubarb, Brazilian,

Known to many as Gunnera, this was once a rare and amazing sight. Now this huge perennial has become quite naturalised, particularly in the west of Ireland where its densely-packed inflorescences of 1mm, stalkless flowers are borne in 1m-long, cone-shaped panicles; without petals, they have tiny, reddish-brown sepals. They flower in July and August. The long, stout stems arise from rhizomes. The leaves are 2m-wide, toothed and palmately-lobed and are on stout stalks which have green bristles. They are very quick-growing in spring. This plant favours damp fields, ditches, coastal cliffs, river-banks, derelict gardens and hillsides. It is a perennial, introduced from Chile – also known as Chilean Rhubarb – and it belongs to the Gunneraceae or Giant-rhubarb family.

My first record of seeing this plant was in Derrynane, Co Kerry in 1952 and I photographed it in Lismore, Co Waterford in 2013.

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

Originally introduced into Ireland as a desirable, architectural, garden plant, Gunnera tinctoria is now recognised as a potentially invasive, colony-forming threat to our native flora. This vigorous plant produces masses of seeds – in excess of 80,000 seeds per seed-head - which are spread by birds. It is also able to reproduce rhizomatically and is therefore extremely difficult to eradicate.