The Cup of Gold is a tropical plant native to Mexico, which was brought to Hawai'i as an ornamental. It is an absolutely amazing vine that can grow up to 40 ft tall or 200 ft long.
The Cup of Gold vine has dark green leaves 6 to 7 inches long and 3 to 4 inches wide. The vine produces absolutely huge flowers - that are 5 to 7 inches across and up to 9 inches deep. The coconut scented flowers are very fragrant, especially in the evening. The flowers can be picked while still closed and will open within a few hours of picking, or they can be picked open. Flowers will last a few days in water. The flowers have a thick, leathery skin and are very sturdy.
Unfortunately the Cup of Gold is an invasive vine and should be destroyed if found growing in the wild. The vine itself is very heavy and requires sturdy support. They tend to grow up on 'Ōhi'a and other trees and can choke the tree and eventually take over large areas. Maui has a great deal of Cup of Gold in the wild, and the Big Island has Cup of Gold in Akaka Falls and other places, as well as in gardens and yards (the one pictured here is from my own yard).
Note: The entire plant, including the leaves and flowers are poisonous if eaten.