Cleistocactus strausii - Silver torch

Cleistocactus strausii is an elegant columnar cactus covered in silvery wool, originating from the Andes mountain range. It forms slender, upright stems that reach towards the sky, luminous and striking from afar in a rocky landscape. Though soft in appearance, covered in fine silvery down, it still bears short, rigid thorns that require caution. Patient and attentive gardeners may enjoy its beautiful red flowers in June. This lovely, not very hardy species is easily grown in pots and should be overwintered indoors outside the Mediterranean coastal region.

Cleistocactus strausii, from the Cactaceae family, is a columnar cactus native to the mountainous regions of Bolivia, particularly the Tarija department, and northern Argentina. It thrives at altitudes between 1,500 and 3,000 metres, often on cliffs bordering watercourses. This botanical species features erect, slightly greenish-grey stems, reaching up to 3 metres in height in the wild, with a diameter of around 6 cm. In cultivation under our climate, it rarely exceeds 2 metres in height. Over time, it produces offsets at the base, forming dense clumps that enhance its architectural habit. Its stems are lined with 25 to 30 longitudinal ribs, densely covered in areoles bearing four central yellow-brown thorns, up to 4 centimetres long, surrounded by 20 shorter, white radial thorns. They almost disappear within the dense silvery hair, a characteristic of the species. The flowers typically appear on specimens aged over 10 to 15 years and at least 45 cm tall. They are tubular, burgundy-red, and around 6 cm long. They emerge horizontally from the stems in June, opening only partially to reveal the stamens and style. Fruits are rare in cultivation—these are spherical, red, 2 cm diameter berries. The root system is adapted to well-drained soil, essential to prevent rot in case of excess moisture.
Despite its delicate appearance, Cleistocactus strausii can tolerate temperatures as low as -8/-10°C in dry soil, a remarkable adaptation to the climatic conditions of its native habitat. In our wetter winters, protection is advisable below -5°C.

Stunning in a minimalist setting, glowing against a backdrop of rocks and blue sky, this candelabra cactus naturally structures rocky landscapes, contemporary designs, and of course large Mediterranean rockeries. Paired with Agave ovatifolia, with its blue-grey rosettes, it creates a balance between rigidity and softness. It also complements Dasylirion miquihuanensis, whose long, slender leaves add a fluid dynamic to the composition. In pots, on a sunny terrace, it stands out as a living sculpture, alone in a simple terracotta container. To enhance its "desert" appeal, it can be staged with Aloe polyphylla. Playing with light and form, Cleistocactus strausii becomes a centrepiece in an arid bed, evoking the Andean landscapes.