The umbel of a Pelargonium triste inflorescence usually consists of 6 to 20 flowers. The flower tube is about 3 cm in length. Flower colour is pale yellow here, on some plants nearly white, or even pale pink.
The petal markings are narrow and purplish, sometimes maroon or dark blue. These dark lines occur only on the lower three petals of the flowers in picture.
Pelargonium petal markings in other species are often restricted to the upper (posterior) petal pair, while the lower (anterior) trio of petals is unmarked; just the opposite of what is seen on these P. triste flowers.
The posterior petals are broader than the anterior ones here, variably obovate with entire margins. Some fairly short, yellow-anthered stamens and a tiny, branched stigma are visible in some of the flowers.
Flowering begins at the end of winter and carries on through summer (Manning, 2007).