Darwinia hortiorum is an erect to spreading, densely branched shrub with a compact habit. It typically grows to a height of and a width of . The glabrous plant is single-stemmed at the base with spreading main branches bearing many ascending, leafy branchlets with pale stems. Older stems have a covering of reddish-brown, papery bark that peels off in flakes. The leaves are arranged alternately, widely spaced, narrow egg-shaped to almost linear, long and wide. The inflorescences appear at the ends of the branches and are composed of groups of 14 to 22 flowers. Each flower has five smooth, glossy, yellowish petals tinged with crimson, five warty dark green sepals with prominent oil
glands and two papery brown bracteoles. Ten
stamens protrude between the petals and the
style is curved towards the centre of the inflorescence. Flowering occurs between late September and early December. The plant is distinctive with no obvious close relatives, although it superficially resembles
Darwinia thymoides which is found in the same habitat. ==Taxonomy and naming==