From four to twelve Mystacidium gracile flowers grow in an inflorescence that becomes 4 cm to 5 cm long. A few of them are produced per plant. The flowers are borne in two ranks, opening from the apex of each drooping flower spike. The bracts are tiny, papery and mostly tubular.
The flower colour is pale yellow-green to nearly white. A flower becomes from 9 mm to 14 mm wide. The dorsal sepal is strap-shaped, the laterals rhomboid or diamond-shaped, the petals smaller than the sepals.
The lip is three-lobed, the midlobe deflexed with an acutely pointed tip; those on the sides very small, positioned next to the spur mouth. The straight white spur of up to 2,5 cm long grows from the lip.
Blooming happens in late winter and spring (Pooley, 1998; www.orchidspecies.com; www.africanorchids.dk).