The flowers of Dianthus bolusii grow in a branched inflorescence of about 20 cm long. The long, thin calyx tube is cylindrical. It is bluish grey in colour, about 2,5 cm long and surrounded by some bracts at its base.
The corolla is sometimes white as seen here, often dark pink to purple with darker marks near the petal bases. The five petal tips are conspicuously fringed or lacerated, more than deeply toothed. The petals are oblong, curving down lengthwise. A couple of slight, longitudinal channels are just visible upon their surfaces. The flower is about 1,5 cm in diameter.
Five stamens of unequal length are visible in the photo, their anthers white. Dianthus flowers have ten stamens, (some of them) often hidden inside the tube. The style is divided into two branches.
Flowering happens in late spring and summer (Vlok and Schutte-Vlok, 2010; iSpot).