The Debe Nek arctotis is a small perennial herb, growing 100–200 mm in height, with widely spaced branches, and forming patches that grow about 1 m wide. The stem, which is robust, woody and flat-growing (prostrate) is frequently slightly below the ground surface. The internodes are indistinct, 5–8 mm wide. The roots are elongated, fibrous and adventitious, and are produced along the stem and from the terminal rosette. The leaves are alternate, pointing upwards (ascending) to spreading sideways (patent), forming a terminal rossette. The old leaves remain after withering. The petiole is 10–30 mm long and occasionally reddish-purple on the upper side. 

The leaf blade is 60–120 × 20–40 mm, egg-shaped (obovate) to divided into lobes with a large, rounded terminal lobe and small lower lobes (lyrate pinnatifid), leathery, yellowish to bright green. The upper surface is rough and hairy, the under surface is densely covered in a mat of white woolly hairs. The margins are slightly rolled under and have pointed or rounded teeth that end in a short sharp point (mucronate). The leaves at the base of the flower stalk (peduncle) are narrow-linear, measuring 20–350 mm.

The peduncle is slightly longer than the leaves, growing up to 170 mm in length, and is upright at flowering, gradually increasing in length and eventually lying flat on the ground when the fruits are mature. The flower heads are at the tip of the peduncle, cup-shaped, 12–15 × 15–20 mm, daisy-like with yellow ray florets and yellow disc florets, the ray florets are reddish-purple on the underside. The fruits (cypselas) are oblong, glossy black or brownish black, wrinkled and ribbed, up to 2.5 × 1.4 mm with no pappus. Flowering occurs mainly in spring to early summer (September to December).

Arctotis debensis may be confused with Arctotis arctotoides and Arctotis microcephala, they have a similar habit, but A. debensis can be told apart because it is larger in all parts and its leaves are leathery and the upper surface is rough to the touch (scabrous).