The flowers are arranged in one or two racemes in axils or on the ends of branches with one or two heads on a peduncle 5–14 mm (0.20–0.55 in) long.

[2][3][4][5] Acacia ascendens was first formally described in 1990 by the botanist Bruce Maslin in the journal Nuytsia from specimens he collected in Chiddarcooping Nature Reserve, about 70 km (43 mi) north east of Merredin in 1989.

[5][6] The specific epithet (ascendens) means 'ascending',[7] and refers to the characteristic orientation of the phyllodes.

[5] This species of Acacia grows in woodland or low scrub on the scree slopes of breakaways and is only known from the Chiddarcooping Nature Reserve.

[2] Acacia ascendens is listed as "Priority Two" by the Western Australian Government Department of Biodiversity, Conservation and Attractions,[2] meaning that it is poorly known and from only one or a few locations.