This is a phenomenon that happens once in 40 - 60 years, but for a short time.
Images of Black Bamboo Flowering in the UK
Black Bamboo (Phyllostachys nigra) flower & dies
The black bamboo flowers every 40 to 60 years, Every black bamboo plant in the UK will flower at the same time.
After flowering, that generation of black bamboo plants will die completely.
The seeds can be collected and planted to start a new stand of bamboo growth.
Also, cuttings from the rhizomes can be used to grow a new generation of plants.
Cultivars of Black Bamboo
|Phyllostachys nigra 'Megurochiku'