Xerophyte

Central Spines

5, yellowish, to 1 cm long.

Description

Cleistocactus ritteriSN|6924]]SN|6924]] is a shrubby columnar cactus, branching basally with more or less erect branches, over 1 metres tall. It has attractive bristly soft spines and lemon yellow blooms.

Flowers

Pointing sidewards or slightly downward, slightly bent, greenish yellow to lemon yellow, to 4 cm long with green stigma lobes.

Ribs

12-16.

Stem

Slim, erect or arching, bright green, to 1 metre tall, 2-3 cm in diameter.

Radial Spines

As many as 30, fine, hair-like white up to 3 cm long (mostly less than 1.5 cm long). The dense spination it possesses, which serve to protect it from the harsh sun common to its native habitat. More precisely the spines benefit the plant by reducing sun exposure and by trapping a layer of air next to the cactus body. This helps to cool the plant in the summer and keep it warm in the winter.

Fruits

Globose, yellow, to 1.5 cm in diameter.

Areoles

Close set, at first dark brown becoming greyish white.