Sydney's ultra-rare Corpse Flower blooms after 15 years [video]
youtube.comthey're not ultra-rare, nearly every major botanical garden in the world has one. They all bloom roughly on a schedule, about 5 of them around the world every year (beyond the fact they also grow in the wild in Sumatra).
If you've ever stood by a blooming plant of this species, it's quite an experience. Not only is it huge, you get occasional "wafts" of smell, which alternates between feces and death.
Fun fact, the scientific name means "malformed penis".
We probably disagree what ultra rare means. They're significantly less common than rhododendrons. They're more common than Wollemi pines.
It's headline hyperbole. They aren't common, any more than hothouse structures capable of growing them are. Same with giant lilypads (for instance).
Fruit bearing Banana plants and Cocoa pods are rare enough in Britain that Kew and Edinburgh Botanical gardens used to have little movable arrows on sticks to show you the fruit if you walked around the hothouse. Same with giant bamboo to show you how fast it grew in a day: if you came morning and afternoon same day you could see the growth.