Rhizomatous plant 50-100 cm. Leaves sword-like, slightly glaucous, 50 cm x 2,5 cm. Upper stem leaves smaller than basal ones. Flowers blue-purple, nearly 6-7 cm long, solitary or 2-3 in a raceme. V - April-October. Fl - in June-July for 2-3 weeks. Fr - August-September. Frost-resistant, tolerates shade. Propagation by seed and division. Z 4 (3).

Siberia (eastern regions), Far East (Primorie, Kuril Islands), northeastern China and Japan. Forest margins, birch woods, dry and wet meadows, peat bogs.