Like Lilium longiflorum, which is often seen offered for sale, each blossom of the Formosa lily has six white petals, but their outer surfaces are marked with conspicuous purple lines.
台灣百合外型與市面上常見的鐵炮百合相仿，每朵花具有六片白色花瓣，但台灣百合花瓣外側妝點著鮮明的紫紅色條紋，花朵可以維持七天左右。