Many of the Grevillea species on display originate from the more arid regions of Western Australia or South Australia, in sandy or gravelly soils. Therefore they do not thrive in the wetter climate and heavier soils at Mount Annan, and have been grafted onto other species to improve their chance of survival. Most of the grafted specimens here have been grafted onto Grevillea robusta (silky oak), a tree with a truly robust character.
If you look at the base of the plants, you will be able to see a line where the two species have been joined. The traditional ‘whip and tongue’ method of grafting has been commonly used, any leaves which sprout below the graft belong to the rootstock and should be pinched off.