Gunnera Passage
A visit to Trebah during summer would not be complete without experiencing the green twilight world of the Gunnera Passage
Much loved by children and adults alike, and situated between Azolla Pool and Mallard Pond, the walkway takes you through a towering tunnel of ‘Giant Rhubarb’ or ‘Elephant’s Rhubarb’. When it rains you can take shelter beneath them or on a hot day, the leaves create welcome shade. It is considered one of the finest displays of gunnera in the country.
This South American native has absolutely enormous leaves, borne aloft on thick succulent, prickly stems. It starts growing from ground level each spring and, within a few months, has reached metres in height, before the stems collapse under the weight of the leaves in autumn. The garden team then cut it back to neaten the plantation up, ready for winter.
A dense plantation of gunnera was created in 1950s, with a passage cut through it for visitors in 1986. Photos from the 1930s showing established gunnera in the garden, so it was likely introduced well before then.
Originally thought to be Gunnera manicata, modern day testing shows that specimens in the UK are actually a cross between the Brazlian manicata and the Chilean tinctoria, leading to it being reclassified as Gunnera x cryptica.
In December 2023, Gunnera x cryptica was classed as invasive in the UK, due to tinctoria also being invasive, so its sale and cultivation is now banned. Thankfully, however, it does not have to be destroyed and we can continue to grow it in the garden.
