Light: Full sun during fall and winter; afternoon shade helps protect plants from intense late-spring and summer heat.
Water: Water deeply and regularly during active growth, allowing the soil surface to dry slightly between waterings. Avoid drought stress during bud formation; reduce watering during summer dormancy without letting roots become completely dry.
Soil: Deep, fertile, well-drained soil enriched with compost. Mulch to conserve moisture and cool roots, keeping mulch away from the crown.
Mature size: 3–5 feet tall and 4–6 feet wide; flowering stalks may reach 6 feet.
Bloom: Buds typically develop in spring, with purple flowers opening in late spring or early summer if left unharvested. Flowering depends on cultivar, planting time, and winter chilling.
Evergreen / deciduous: Herbaceous perennial; often summer-dormant or short-lived in Phoenix heat, and sometimes grown as a cool-season annual.
Growth rate: Fast during cool weather with adequate water and fertility; slows or stops during extreme summer heat.