This is the simple key I could build based on Hortus Third, Manual of Cultivated Plants this website and other sources. You may refine it if you like: Key to the commonly cultivated species of Crocosmia 1a. Perianth tube twice or more as long as lobes....................................................................(2) 1b. Perianth tube shorter or equalling lobes...........................................................................(4) 2a. Inflorescence many-flowered, unbranched, one-sided......................................................C. masoniorum 2b. Inflorescence few-many flowered, branched.....................................................................(3) 3a. Inflorescence forking, 15-25 cm long; perianth bright orange-yellow, tinged ed...............C. pottsii 3b. Inflorescence much-branched, with often brush-like clusters of flowers............................C. paniculata 4a. Flowers orange yellow........................................................................................................C. aurea 4b. Flowers crimson to orange-crimson...................................................................................C. crocosmiiflora |