The flower that only blooms every 40 years is the Titan Arum flower.
The Titan Arum is also called corpse flower, herbaceous flowering plant of the arum family and is known for it's massive foul smelling inflorescence cluster of flowers.
The flower that only blooms every 7 years is the Giant Himalayan Lily which is a pretty rare plant that flowers only once in every 7 years and then dies.
The flower that blooms only once are the Monocarpic annuals flowers.
The Monocarpic annuals flowers consist of plants that germinate, grow, flower, produce seed and die within one growing season and sometimes within only a few months or even weeks.
Monocarpic plants are those plants which flower, produce seeds then die.
Hence, annual plants are often termed as monocarpic.
The terms semelparous and hapaxanth also mean an equivalent as monocarpy.
All annual (eg- Wheat, Rice) and biennial plants (eg-Carrot, Radish) are monocarpic.
A few perennial plants(Bambusa tulda , Agave, Banana, etc) are also monocarpic.
All annual (eg- Wheat, Rice) and biennial plants (eg-Carrot, Radish) are monocarpic.
A few perennial plants(Bambusa tulda , Agave, Banana, etc) are also monocarpic.
Monocarpic plants are those that reproduce generatively only once per lifespan, and then die.
Annual plants last one season, in which they seed and die, whereas biennials flower, seed and die in their second season.
All monocarpic perennials spend more than a year in a vegetative stage before flowering once and then dying.
Monocarpic perennials are mostly herbs and shrubs.
The length of the vegetative period can be highly variable between plant species, from strictly biennial to long-lived monocarpic perennials.