Rhizomes knobbly, woody. Roots tough. Leaves grayish green, linear, 20--50 cm × 3--4 mm, few veined, base surrounded by brown, persistent sheaths. Flowering stems 10--15 cm; spathes 3, yellowish green, ovate or broadly lanceolate, 6--8 × 2.5--4 cm, inflated, 2-flowered, transverse veins conspicuous between parallel veins, apex long acuminate. Flowers pale violet, 6--7 cm in diam.; pedicel 1--1.5 cm. Perianth tube 2.5--4 cm, slender; outer segments narrowly spatulate, 3.5--5 cm × 8--10 mm, midvein papillose; inner segments narrowly lanceolate or broadly linear, 3.5--4 cm × 7--8 mm. Stamens 3--3.5 cm; anthers yellowish purple. Ovary ca. 1.5 cm × 2.5--3 mm. Style branches 3.5--3.8 cm × ca. 6 mm. Capsule ellipsoid-cylindric, 2.5--4 × ca. 1 cm, 3-angled, 6-veined, angles thickened, apical beak 2--4.5 cm. Fl. May, fr. Jul--Aug.