The two subspecies differ primarily in leaf size and shape. Grevillea obtusiflora subsp. obtusiflora
G. obtusiflora subsp. obtusiflora is a low, multi-stemmed shrub, growing to 0.2-0.4 m high. Its leaves are narrowly obtuse-elliptic to oblong, and 2-5 cm long and 1.5-5 mm wide. Flowers are pink to pinkish red and cream. It flowers sparsely in winter and spring, between July and October, with flowering peaking in September. It is not known to set fruit or seed (Makinson 1997), but regenerates from root suckers.
Grevillea obtusiflora subsp. fecunda is a low, spreading to erect shrub growing up to one metre high. It flowers profusely with crimson to deep pink and cream flowers in spring. Its leaves are linear to very narrowly obovate, 1.5-4.0 cm long and 1.0-1.2 mm wide. Fruit sets freely (Makinson 1997).