Say it: oh-breh-GOH-nee-uh deh-NEG-ree-eye. Common names: artichoke cactus.
Where it grows
A single valley in Tamaulipas, northeastern Mexico, on limestone hills. With such a tiny range it's listed as endangered in the wild, and like Ariocarpus it's CITES Appendix I, so our seed ships within the US only.
Size and growth
A flat rosette of overlapping, triangular grey-green tubercles that really does look like an artichoke, 4–8 inches across, over a thick taproot. Slow: a decade or more to reach flowering size on its own roots, which is why it's so often grafted.
Flowers
White to pale pink flowers from the woolly center in summer, followed by small fruits buried in the wool.
Care
- Light: full sun to bright light.
- Water: sparingly in summer, dry in winter. Rot-prone if cold and wet.
- Soil: mineral mix in a deep pot for the taproot.
- Cold: tolerates light frost if bone dry, but safer above freezing.
From seed
Moderate. Germination in 10–30 days; seedlings are tiny and slow. Treat them like Ariocarpus: a long stay in the humid tray, then very gradual hardening.