Even if you aren’t familiar with the genus Passiflora, you are probably aware of the fruit of the cultivated Passiflora edulis: passionfruit. The plant in the photograph is a different species, and is commonly known as fragrant granadilla.
It is also cultivated, but only as a fresh fruit (see: Fruits from America: An Ethnobotanical Inventory – Passiflora alata.
This particular plant was photographed in a non-public glasshouse at the garden. We unfortunately do not have a public display glasshouse (yet), which would be ideal for showcasing plants such as these.
P.S. Note the photographer’s prop in the upper left: flagging tape to suspend the viny stem from a pipe so as to be able to photograph inside the flower…