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Silky Oak

Grevillea (greh-vil-LAY-ah)

Family: Proteaceae Unknown Understory (15-40 ft)

Spider flowers are a genus of about 360 species of evergreen flowering plants in the Proteaceae family. Most of them are native to Australia but a few are found in New Guinea and New Caledonia. They vary greatly from being trees to erect shrubs to cascading in form. They are evergreen plants that appreciate warm temperatures and long growing seasons. Most varieties will not survive freezing temperatures. but a few tolerate some cold such as G. victoriae and have been grown on the Pacific coast of CA and OR. The genus was named in honor of Charles Frances Greville, an 18th-century patron of botany and co-founder of the Royal Horticultural Society. The leaves can be either simple or compound and alternate on the stem with either a needle-like or fern-like appearance and stay attractive all year. The flowers can be small to spectacular and most have nectar that attracts hummingbirds and pollinators. The flowers are petal-less, but the narrow calyx tube produces long styles that are typically brightly colored. Most of these plants require acidic well-drained soils low in phosphorus. Do not use a fertilizer with phosphorus in it. They need full to partial sun and most are drought-tolerant. In NC grow them in containers so they can be moved inside when temperatures approach freezing. They can be grown as a houseplant in a spot with bright light or in a greenhouse or atrium-type setting. Insects, Diseases, and Other Plant Problems: Handle with care - skin irritation can be severe.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 50 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Fills a similar niche Lantana camara 'Miss Huff' Nerium oleander Pelargonium x hybridum

Full plant profile

Growing Conditions
Plant type
Poisonous
Life cycle
Perennial; Woody
USDA zones
9a, 9b, 10a, 10b, 11a, 11b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage
Available space
12 inches-3 feet; 3 feet-6 feet
Mature size
Height: 3 ft. 0 in. - 20 ft. 0 in. | Width: 4 ft. 0 in. - 20 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Cascading; Clumping; Erect; Multi-stemmed
Texture
Fine
Foliage
Broadleaf Evergreen
Leaf color
Blue; Gray/Silver; Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately); Simple
Leaf arrangement
Alternate
Leaf margin
Lobed
Leaf feel
Soft
Hairs present
No
Leaf detail
Fern-like to needle-like leaves can be either simple or compound and are alternate on the stem. They stay attractive year-round and vary in size per species.
Flower color
Gold/Yellow; Orange; Red/Burgundy; White
Flower value
Fragrant; Good Cut; Long-lasting; Showy
Flower form
Spike
Flower shape
Tubular
Flower detail
Flowers are arranged in a terminal cluster, tubular shaped and may be white, red, yellow, or orange. They can be small spider-like or large toothbrush shaped with a large caylx covered with protruding filaments on one side and no petals. Most have a long bloom season
Bloom time
Fall; Spring; Summer; Winter
Fruit type
Follicle
Fruit detail
A follicle that spits down 1 side releasing 1-2 seeds.
Wildlife & Ecology
Native status
Unknown
Origin
Central Malesia to New Guinea, New Caledonia, Australia
Attracts
Hummingbirds
Food & Medicine
Fruit type
Follicle
Landscape Use
Landscape location
Container; Houseplants
Landscape theme
Drought Tolerant Garden
Design feature
Specimen
Garden tags
#poisonous #showy flowers #low maintenance #fragrant flowers #evergreen #well-drained soil #full sun tolerant #houseplant #container plant #contact dermatitis #long bloom time
Problems & Resistance
Problems
Contact Dermatitis; Poisonous to Humans
Resistant to
Drought
Poison severity
Low
Poison parts
Bark; Flowers; Leaves
Poison symptoms
Intense itching, streaking, and blisters, often delayed after contact.
Toxic principle
Resorcinols, pentadecylresorcinol, tridecylresorcinol
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Bark; Flowers; Leaves; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.