The red flowers of Watsonia angusta grow in a spike in two opposing vertical arrays. The flower has a narrow, downwardly curved tube of about 4 cm in length. The tepals, joined in the lower part of the tube, open to a corolla diameter of 3 cm at their rounded tips. The dark anthers and branched style can be observed in this photo.
Blooming happens from late spring through summer. This plant was flowering already in September near Oudtshoorn, producing orange flowers (Bond and Goldblatt, 1984; Vlok and Schutte-Vlok, 2010).