It is an herbaceous perennial plant growing from tuberous roots, with stems 40–150 cm (16–59 in) tall. The leaves are linear, 50–90 cm (20–35 in) long and 1–2.8 cm (0.39–1.10 in) broad. The flowers are 5–12 cm (2.0–4.7 in) across, orange-red, with a pale central line on each tepal; they are produced from early summer through late autumn on scapes of ten through twenty flowers, with the individual flowers' opening successively, each one only lasting one day. The fruit is a three-valved capsule 2–2.5 cm (0.79–0.98 in) long and 1.2–1.5 cm (0.47–0.59 in) broad which splits open at maturity to release the seeds.
