Dominic Whitmee Chief Executive of the Ornamental Aquatic Trade Association (OATA) has advised retailers, “Not to stock or sell any giant Gunnera species because, unless their suppliers can prove provenance, it may be a hybrid species.
Defra has informed us that the cross of G. manicata and G. tinctoria is banned from sale because hybrids of a parent that is banned, in this case G. tinctoria, are also banned under the Invasive Alien Species (Enforcement and Permitting) Order 2019. Although legally, G. manicata can still be sold, we advise it is removed from sale because it is highly unlikely to be pure and it is very difficult to accurately identify young plants”.
In December 2023, a UK ban on Gunnera was reported as researchers discovered that the plant often listed as the benign Gunnera manicata, was in fact an invasive hybrid (Gunnera × cryptica), which is listed as a ‘species of union concern’ in the UK and EU. Defra has confirmed that these hybrid plants should therefore not be sold.
Whitmee added, “We are currently working with DEFRA to understand the invasive potential of the cross and whether trade restrictions are justified.”
For reference, relevant research papers on Gunnera:
- An investigation of large-leaved Gunnera L. (Gunneraceae) grown outside in Britain and Ireland | Sibbaldia: the International Journal of Botanic Garden Horticulture, The Royal Botanic Garden Edinburgh, December 2023.
- A new spontaneous hybrid in GunnerasubgenusPanke(Gunneraceae)widespread in the British Isles, with notes on the typification of G. manicataJulianM. H. Shaw*, DawnEdwards, JohnDavid, Royal Horticultural Society, Wisley, Woking, Surrey, U.K
- The large Gunnera’s (G. tinctoria and G. manicata) in Europe in relation to EU regulation 1143/2014, Johan L. C. H. van Valkenburg ,Bruce A. Osborne,Marcel Westenberg, PLOS One, April 20, 2023.