Echinopsis spachiana
Light: Full sun to light shade; afternoon shade helps prevent scorching in Phoenix, especially on young or newly planted specimens. Acclimate gradually to direct sun.
Water: Low water once established. Water deeply but infrequently during warm weather, allowing soil to dry completely between waterings. Keep nearly dry in winter.
Soil: Very well-drained, sandy or gravelly soil. Use a fast-draining cactus mix in containers; avoid heavy soil and locations that collect runoff.
Mature size: Typically 5–7 feet tall and 3–5 feet wide as a mature clump; occasionally taller under favorable conditions.
Bloom: Late spring through summer on mature stems; flowers open at night and usually fade the following day.
Evergreen / deciduous: Evergreen.
Growth rate: Moderate to fast for a columnar cactus with warmth and appropriate summer watering.