Native to Australia. Many species and hybrids. Plants vary in size and appearance but generally have fine-textured foliage and long, slender, curved flowers, usually in dense clusters. Provide good drainage. Like other members of the protea family, grevilleas are sensitive to high levels of phosphorus in the soil, so feed lightly and avoid fertilizers with high phosphorus content. Intolerant of salt. Seldom browsed by deer.
G. banksii. BANKS GREVILLEA. Shrub or small tree. Zone TS; USDA 10-11. Often sold as G. banksii forsteri. To 920 ft. tall and 912 ft. wide. Leaves 410 in. long, deeply cut into narrow lobes. Erect, 3- to 6-in.-long clus-ters of dark red flowers appear sporadically all year; bloom is heaviest in late spring. Showy used singly against a high wall, near an entryway, or grouped with other big shrubs. Freezes at 24F but tolerates wind. Full sun. Little to regular water.
G. 'Canberra Gem'. Shrub. Zone LS, CS, TS; USDA 8-11. Open, graceful growth to 8 ft. tall, 12 ft. wide. Bright green, needlelike, 1-in. leaves. Clusters of red flowers in spring (and intermittently at other times). Full sun or partial shade. Moderate water.
G. 'Noellii'. Shrub. Zones, LS, CS, TS; USDA 8-11. To 4 ft. tall, 45 ft. wide. Densely clad with narrow, inch-long, glossy medium green leaves. Clusters of pink-and-white flowers bloom in spring. Takes light shearing well; good as formal or informal hedge. Full sun or partial shade. Moderate water.
G. robusta. SILK OAK. Tree. Zones CS, TS; USDA 9-11. Fast growing to 75 ft. (rarely to 100 ft.) tall. Symmetrical, pyramidal when young. Old trees are broad topped (4050 ft. wide), usually with a few heavy horizontal limbs; picturesque against skyline but too large for most home gardens. Fernlike leaves are golden green to deep green above, silvery beneath. Heavy leaf fall in spring, sporadic leaf drop throughout the rest of year. Large clusters of bright golden orange flowers in early spring. Wood is brittle, easily damaged in high wind. Young trees are damaged at 24F; older ones are hardy to 16F. Use for quick, tall screen, or clip as tall hedge. Full sun. Grows in poor, heavy soils if not overwatered; can take regular water in fast-draining soils.
G. rosmariniifolia. ROSEMARY GREVILLEA. Shrub. Zones LS, CS, TS; USDA 8-11. To 6 ft. tall, nearly as broad. Narrow, 1-in.-long leaves are dark green on top, silvery beneath; look a bit like those of rosemary (Rosmarinus). Red-and-cream flower clusters (rarely pink or white) in fall and winter; scattered bloom in other seasons. Use as clipped or informal hedge in dryish places. Impervious to heat and aridity. A dwarf form, 3 ft. high and 6 ft. wide, bears pink-and-cream flowers in waves throughout the year, most heavily in spring and fall. 'Scarlet Sprite', another dwarf, is similar but bears blooms in bright red and cream. Full sun or partial shade. Little water.