This grower is sure of this plant identification.
Divided from main plant in spring (label shown from main plant).
4 litre pot bit plant only fills 3/4 of this.
Jian zhu, Arrow bamboo
Fargesia genus (Jian zhu). There are more than 80 species in this genus of clump-forming evergreen bamboos from damp woodland in central China, Vietnam and the eastern Himalayas. These often vigorous bamboos are grown for their attractive bright to dark green leaves and erect canes.
They are among the world's hardiest bamboos, with some withstanding temperatures down to -25C or more.