Aspalathus quartzicola is a mat-forming shrub, with branches densely packed and growing up to 20 mm high. It has distinct twisted stems of 30 mm thick (stems look like ancient tree stumps). It is a respouter, as it dies after fire and regenerates from burned stems. Leaflets are linear, succulent, upright and hairless, arranged in dense clusters.

The inflorescence is 1- or 2-flowered and flowers are found on the ends of the shoots arising along the branches. The flowers form a typical pea flower, are white with a distinct pink keel tip and have a sweet-smelling scent. This species flowers from August to September (in spring).

Its fruits are borne upright; they are flatly egg shaped, hairless, and glossy, with a sharp point and covered with a network of veins. When fruits are young they are bright green and then turn pale brown when mature (7 × 3 mm). Seeds are 2.0–2.3 × 1.8–2.0 mm and tan with brown blotches.

Aspalathus quartzicola is a long-lived plant, with an estimated life span of 40 years (Curtis et al. 2014).