Aristolochia gigantea has one of the largest of all the Aristolochia flowers, up to 36cm long and 30cm wide, and is pollinated by flies; but does not emit a malodorous smell like others in the genus.
Flies are attracted to the sight and smell of the open flower, and land on a slimy lip at the centre of the flower, following the scent down the central passage and into a bladder-like trap.
Here, they can't escape, due to dense downward-pointing hairs that prevent the fly from climbing out.
Now fully incarcerated, the fly must wait until the pollen is ripe, usually the next morning before the hairs start to wilt, at which time the fly can escape.
To ensure the prisoner or guest is happy while incarcerated, the flower produces nectar to keep them alive and well.
The fly will then find another flower and repeat the process, taking pollen from the previous flower to pollinate the next flower.
•Fast growing climber reaches five to seven metres in a cool conservatory.
•Needs wires, trellis or a pole to be trained around, for support.
•Prefers temperatures above 15degC. Heart-shaped leaves up to 15cm long.
•Native to southern and central America.
•Grows in full sun or part shade.
-Stephen Bishop is curator of the winter garden glasshouse at Dunedin Botanic Garden.
