Cactus- Obregonia denegrii| Artichoke cactus; Seedling (2.5" pot)

Obregonia denegrii—the sole species in its genus, named for Mexican president Álvaro Obregón and agriculture minister Ramon P. De Negri—is an artichoke-shaped cactus whose overlapping, triangular tubercles spiral into a tight, sculptural rosette. What makes it special is its unmistakable geometric form, disproportionately large white flowers that crown the plant in summer, and its status as a rare, slow-growing collector's prize from the limestone hills of Tamaulipas, Mexico. Grow it in a deep pot with gritty, calcareous, fast-draining soil, give it bright filtered light, water moderately in summer, and keep it bone-dry in winter above 40F.