I visited the Denver Botanic Garden yesterday. It has a fantastic conservatory with one of the best rainforest displays of any garden I've ever visited (including Kew and the San Francisco Conservatory of Flowers).
There was also a bonsai collection, a Japanese tea garden, herb and prairie gardens, a scripture garden and an amphitheater. Unfortunately I only had my phone with me to take pictures.
I moved to a new apartment in San Francisco with a large balcony. I've planted a hummingbird garden and many passion flowers. One of the first passionflowers to bloom was a Passiflora xdecaisneana 'Purple Tiger'.
P. x decaisneana is listed as P. alata x P. quadrangularis, two similar looking species with entire leaves and long purple and white filaments. This hybrid was first made in the 19th Century and was named for the botanist Joseph Decaisne. The flowers are fragrant and tend to hang down below the leaves
Hummingbirds visit the garden to feed everyday, and sometimes even stop to rest.