Elaeagnus pungens aka Thorny Olive

Elaeagnus pungens is an evergreen shrub called silverthorn or thorny olive. It belongs to the oleaster family, Elaeagnaceae. Its native range includes China, southern Korea, and Japan. It grows on lowland slopes, roadsides, and in thickets. Many sites lie near the sea. In gardens, it reaches 10–15 feet [3–4.6 metres] tall. Its spread can reach 18 feet [5.5 metres]. Some sources report larger plants, reaching 26 feet [8 metres].

The shrub grows fast and forms a broad, dense crown. Long shoots arch outward and give it an uneven shape. Thorny stems can catch on trees and help it climb. Roots send up suckers that extend the clump. Young bark is smooth and reddish brown, with orange lenticels. Older bark becomes scaly. Brown scales coat the young shoots. The leathery leaves grow in an alternate pattern. Their glossy green tops contrast with pale, silvery undersides. Tiny brown scales dot the lower leaf surface. The leaf edges have gentle waves.

Small, pale cream flowers grow in clusters at leaf joints. They have a bell-like shape and a strong scent. Flowers open from October to November. The oval fruits each hold one seed. They turn reddish brown and ripen from March to May. Birds eat the fruit and spread the seeds. People can eat ripe fruit and seeds, raw or cooked. Unripe fruit tastes astringent; ripe fruit has a tart taste. Cooks use it for drinks and preserves. PFAF reports no known hazards. NC State lists it as non-toxic to cats, dogs, and horses.

Grow it in sun or partial shade with good drainage. Shade makes the foliage less dense. It accepts sand, loam, clay, and poor soils. It also tolerates acid, neutral, and alkaline soil. Avoid ground that stays wet or drains poorly. Established plants withstand drought, salt spray, pollution, and deer damage. Missouri Botanical Garden gives USDA zones 7–9. Oregon State reports hardiness to zone 6; RHS rates it H5. Gardeners use it for hedges, screens, windbreaks, and erosion control.

Growth needs frequent pruning where space is tight. Flowers form on older wood. It can escape gardens and crowd out native plants. Several southeastern US states class it as invasive. Serious pest and disease problems are uncommon. Leaf spot, rust, honey fungus, and coral spot can occur. Spider mites may attack stressed plants. Elaeagnus sucker can also affect it.