Synonyms:

Borzicactus strausii
Cephalocereus strausii
Cereus strausii
Cleistocactus nivosus
Demnosa strausii
Denmoza strausii
Echinopsis nothostrausii
Pilocereus strausii
Pilocereus strausii f. cristatus

Habitat:

Cleistocactus strausii is native to Bolivia, where it thrives on rocky substrates of mountainous areas, at a wide range of altitude, on windy spots.

Description:

The Cleistocactus strausii is a striking cactus with a columnar shape that is well-loved in rock gardens by cactus enthusiasts. With a grey-green stem featuring 25 distinct ridges, the plant is defined by its areoles that are covered in white and woolly hair. Each areole hosts four central yellow spines and up to 40 white radial spines. The plant blooms from late spring to late summer, but in cultivation, it blooms plentifully. Its tubular flowers protrude from the apex and its appearance is defined by its purple-red coloring and abundance of hair. It is a member of the Cactaceae family, originating from the mountainous areas of Bolivia, found between 1,500 to 3,000 meters tall.

Also known as the “silver torch”, this plant is known for its tall and slender grey-green stems that can reach up to 3 meters in height but are only 6 cm in diameter. It is a slow grower but its upright habit and silvery coloring make it a spectacular plant to behold. It prefers well-draining soil and lots of sunlight but cannot tolerate high temperatures. In freezing temperatures, it can survive down to -10°C, but overwatering in winter can lead to root rot. When the plant blooms, it produces deep red or burgundy flowers that are approximately 6 cm in length. They protrude horizontally from the stems and barely open, revealing only the style and stamens. When cultivated, the plant blooms frequently.

Cultivation:

Cleistocactus strausii is a sturdy plant that grows rapidly and is often used as a rootstock. Here are some guidelines for its proper cultivation:

It needs full sun exposure like many other cacti.
The temperature should always remain rather high, never dropping below 10°C (6°C for more robust species).
Water moderately in all seasons, being careful not to let water stand. Stop watering completely during winter.
It is recommended to use soil specifically designed for cacti, well-drained, or a mixture of universal soil and sand in equal parts.
To sustain its vigorous growth, it is advisable to fertilize once a month from April to September using a fertilizer rich in phosphorus and low in nitrogen.
You may need to repot the plant annually due to its growth. Remember to wear gloves to protect yourself during the operation, as with all cacti.

Propagation:

Propagation is carried out either by cuttings or by sowing. Cuttings can be also obtained by cutting off the apical part of the stems in Spring and placing it in a sandy, porous substrate to be maintained slightly moist until it has put some roots. Offset might also be used as propagation material. Seeds, instead, should be sown in a well-drained substrate Just drop them on the substrate without burying them and keep it moist until they germinate. The temperature required for germination is around 20ºC.

Curiosity:

The genus name “Cleistocactus” comes from the Greek kleistòs, meaning to close, and refers to the flowers that never fully open.

Official Web Site:
www.giromagi.com

Italian Blog:
www.giromagicactus.com

Tips:
Read our advice