Grevillea hortiorum Olde (Proteaceae: Grevilleoideae: Hakeinae), an uncommon species from winter-damp woodlands in the Avon Wheatbelt, south-west Western Australia.

Grevillea hortiorum Olde, a species in the Triloba Group sensu Flora of Australia (2000), is here described for the first time. Its nearest relative is certainly also a member of the Triloba Group, based on shared morphological characters, and it may be related to Grevillea acrobotrya Meisn. Numerous morphological differences distinguish it, but it has not been tested phylogenetically. Subsequent to its initial discovery when it was thought to be rare, both its distribution and population have been greatly expanded, almost exclusively due to the efforts of its eponymous collectors. It was initially thought to be uncommonly associated with open wandoo woodland but later collections have been gathered in open heath as well. An interim key to the species is provided.