The white, cream and occasionally pale pink flowers of Pelargonium caucalifolium subsp. caucalifolium grow on long pedicels in few-flowered umbels. Sharply pointed, narrow sepals, olive green with tinges of purple and pale, hairy margins are visible behind the corolla of the flower in picture.
In the corolla the upper pair of petals are large with angular, often oblique and sometimes rounded tips. On these two upper petals dark purple to maroon line markings spread from two points on each petal base along the vein lines across the lower petal parts. The lines stop less than halfway to the tips, losing colour higher up, while the veins remain visible across the near white to pale cream petal surfaces. This carries on for some distance, although not quite to the tips.
The lower, smaller pair of petals has narrow blades, broadest in the centre, the tips tapering. Less conspicuous coloured lines, again dark purple to maroon, are present on the lower petals, starting from the base to almost halfway.
Pale purple anthers are visible at the tips of some of the creamy white filaments, the others being sterile. Flowering happens from spring to early autumn. The plant in picture was found flowering during April (iSpot).