Echinopsis sp. (Hedgehog Cactus)

Echinopsis is a diverse genus of cacti in the Cactaceae family, native to South America, especially Argentina, Bolivia, Peru, Paraguay, Uruguay, Brazil, and Chile. Species range from small globose plants that form clumps to large columnar cacti, reflecting a broad modern circumscription that includes groups formerly separated as Lobivia, Trichocereus, and several other genera. Stems are ribbed and usually armed with radial and central spines, although their number, length, and form vary greatly. A characteristic feature is the production of large, funnel-shaped flowers with long floral tubes; many species flower at night with white, strongly fragrant blooms, while others produce spectacular daytime flowers in pink, red, orange, or yellow. Numerous hybrids have been selected specifically for unusually large and colorful flowers.

Echinopsis generally grows best in full sun to bright filtered light and porous, fast-draining cactus soil. Many species come from seasonally dry environments and benefit from regular watering during active growth followed by a distinctly drier winter rest, which can also encourage flowering. Cold tolerance varies greatly with origin and species, so no single minimum temperature or USDA zone reliably represents the genus. Globose species and hybrids are particularly well suited to containers, while the larger columnar species require considerably more space.