A true oddity among cacti, Tephrocactus strobiliformis grows in chunky, scale-like segments that resemble stacked pine cones. Each segment is easily detached and can root to form new plants, making this a favourite among collectors. Its matte grey-green surface is dotted with tufts of short, bristly spines, and while it remains compact, it makes a bold sculptural statement in pots or grouped displays. Scientific Name Tephrocactus strobiliformis (strobiliformis = pine cone-shaped, referencing the form of each segment) Synonyms Sometimes considered a variety of Tephrocactus articulatus Common Name Pine Cone Cactus, Cone Joint Cactus Origin Native to northwestern Argentina – arid, high-altitude regions Light Prefers very bright light and at least 3–4 hours of direct sun per day. A south-facing windowsill is ideal. Gradually acclimatise to avoid scorching. Water Water sparingly. Let soil dry out completely between waterings – typically every 2–3 weeks in summer, less in winter. Overwatering can easily cause rot at the joints. Humidity Low humidity is essential. Avoid misting or grouping with humidity-loving plants. Soil Use a sharply-draining cactus mix with plenty of added grit, pumice or perlite. Terracotta pots are ideal for preventing excess moisture retention. Food Feed once every 4–6 weeks in spring and summer with a diluted cactus fertiliser. No feed in winter. Temperature Happy between 18–28°C. Can tolerate brief dips to 5°C if completely dry. Keep out of frost and draughts. Pet-safe No – mildly toxic if ingested and may have irritating glochids. Sprouts Top Tips Avoid bumping or knocking the plant – its segments detach easily and can be rooted, but sudden movement may cause accidental damage. Extras May produce white to pale yellow flowers in spring or summer, though flowering indoors is rare. Did You Know? Each “cone” segment can grow roots if detached and placed on dry soil – it’s a clever natural method of propagation!
