Weberbauerocereus winterianus

This cactus grows as a set of erect, cylindrical stems about 2 to 3 inches thick, each ridged with 20 to 30 shallow ribs that run the length of the column. Along the crest of every rib sit the areoles, the small cushioned points from which spines arise on a cactus. Here they release a dense coat of golden-yellow spines: stiff central spines up to about half an inch long, surrounded by finer spines that lie flat against the stem. As a plant matures, it branches above the base into several parallel shoots, giving older specimens a candelabra outline. Toward the tips of flowering stems, the areoles produce long, fine, bristle-like golden spines, and it is within these soft-looking zones that the flowers appear. The blooms open at night, reach about 3 inches long, and range from white to faintly pink, with a woolly tube. Rounded fruits follow, green to reddish and about 1.5 inches across, wrapped in dark wool.

In its native range, this species grows on dry, rocky Andean slopes where rainfall is seasonal and sunlight is strong. Its form reflects those conditions. Like other cacti, it uses CAM photosynthesis, a water-saving process in which the plant opens its pores at night to take in carbon dioxide rather than during the hot day, which cuts moisture loss. The thick, ribbed stems act as reservoirs that swell after rain and shrink through drought, while the dense spine coat shades the surface and buffers it from heat. In the garden, this makes an upright, low-water accent for desert and xeriscape plantings, and a strong vertical shape among lower succulents. It needs full sun and fast-draining, gritty soil. Its main limitation is cold: it tolerates only light, brief frost and only when its tissues are dry, so in cooler areas it is best grown in a container that can move under cover, since cold combined with wet soil invites rot.

The genus Weberbauerocereus is a small group of Peruvian and Bolivian columnar cacti considered intermediate between the well-known genera Trichocereus and Cleistocactus. The species name honors Hildegard Winter, a German nursery owner who distributed seeds that her brother, the plant collector Friedrich Ritter, gathered in South America. The pale, night-opening flowers follow a pattern common in columnar cacti, whose evening blooms are typically visited by nocturnal pollinators such as moths and bats, though the specific pollinators of this species have not been well documented. One practical note for handling: the spines are stiff and sharp, and the fine bristles near the stem tips break off easily and lodge in skin. Use thick gloves or wrapped padding when moving or planting it, and site it away from walkways and doorways.