After growing for a few decades, a flower spike of epic proportions arises from a yucca-like trunk.
When young, F. parmentieri forms a rosette of stiff, blue-grey leaves, which mature into a tall trunk felted with the remains of old leaves. After 15 – 50 years it will put out a monstrously huge flower spike, up to 6M tall! This a is monocarpic plant, meaning that the plant dies after flowering. Plants in the same area tend to flower during the same year (a phenomenon known as masting), leaving a sad absence for many years thereafter. Fruits seldom form, and new plants grow from bulbils that form in the axils of the of the flower bracts. So, unusually, vegetative reproduction requires the plant to flower!
F. parmentieri is endemic to the Volcanic Belt of Mexica. It is difficult to say more as the biology has yet to be properly nailed down. Some have it in the Asparagus family, some in the Agave family. And there is considerable uncertainty as to which species are actually distinct, and which merely synonyms. There does not seem to be a common [English] name for any of the plants in this genus.
Soil / Aspect:
F. parmentieri requires dry, free-draining soil. It can tolerate some frost. Apparently there is one in Dunedin Botanic Gardens.
Enjoy it when it flowers! And stick a few bulbils in the ground when the flower fades.