Nothing is known of its origin and as the plant is male (all Smilax species are dioecious) its taxonomic position is uncertain. It is now assumed that our specimen was grown and retained (rather than being actively selected) because it grew so well here. Further investigation by Dr James Cullen has led to the view that it is probably a variant of the North American species S.bona-nox which is known to be extremely variable.
There are currently four plants growing at the Garden. One can be found scrambling over the new railings at the Brookside Gate, two scale the south-east facing walls of Cory Lodge and a final example can be seen in the Systematic Beds.
It is an evergreen, climbing and scrambling plant with spines and tendrils which can hook onto or twine around other vegetation, and it successfully grows up to 8 metres here at the Garden. Small attractive green flowers appear in mid June. It is very straight-forward to grow, being able to cope with even quite severe frosts and can be used successfully against a south facing wall or to cover tree stumps or other unsightly features.