Gunnera tinctoria is a spectacular architectural, herbaceous plant, bearing huge, rhubarb-like leaves which die down in autumn. It needs a lot of space and looks best grown as a specimen plant in a bog garden or at the pond edge, where the reflections from the water reveal the prickly undersides of its leaves.
Gunnera tinctoria has more rounded, deeply lobed leaves than closely related Gunnera manicata, while its leaf stalks are shorter. The flowering spike of Gunnera tinctoria is shorter and its individual spikes smaller and less open than those of Gunnera manicata.
Gunnera tinctoria is considered an invasive plant in the British Isles. A study conducted by the Royal Horticultural Society has found that Gunnera manicata has been lost to cultivation since it was introduced, and that plants thought to be Gunnera manicata are actually a hybrid of Gunnera manicata and Gunnera tinctoria, which has been named Gunnera × cryptica. Sales of all gunneras have since been banned and gardeners with existing gunneras are advised not to let them spread beyond their garden.
If you have a gunnera in your garden and would like to remove it, the best thing to do is cut it back completely and then dig it out. Alternatively, to stop it spreading simply cut flower heads in summer before they set seed, and then compost them carefully, ideally in a closed system.
