Culture
Winter hardy to USDA Zones 4-9 where it is easily grown in average, medium moisture, well-drained soils in full sun to part shade. This is a nitrogen-fixing shrub/small tree that tolerates a wide variety of soils including poor unfavorable ones. It prefers consistently moist soil conditions, but is tolerant of drought. Avoid wet, poorly-drained soils.
A single autumn olive plant can produce an abundant annual crop of edible fruits (to 80 pounds) containing up to 200,000 seeds. Birds and animals consume the fruits and help distribute the seed. Autumn olive has been found to easily out-compete, suppress and displace native plants in the landscape through rapid growth, root suckering, and self-seeding, resulting in the creation of dense shady areas that prevent continued growth of nearby plants which require sunny conditions to survive. This shrub is now listed as an invasive species in a number of States in the central and eastern U.S. including several States where it has been banned for sale, distribution or cultivation.
Noteworthy Characteristics
Elaeagnus umbellata, commonly called autumn olive or autumnberry, is a large deciduous shrub or small sprawling tree of the Oleaster family that typically matures to 10-16’ tall and to 20-30’ wide. It is native to China, Japan and Korea. It was introduced into the U.S. from Japan in 1830, with initial uses including strip mine reclamation areas, ornamental shrub applications and wildlife cover/food. Rapid growth, vigorous growing habits, showy-edible fruits and attractive appearance led the U.S. Soil Conservation Service in the 1950s to recommend this shrub for a number of different purposes including windbreaks, erosion control, highway beautification, wildlife habitat, and wildlife food (fruits). These recommendations were quickly retracted, however, as soon as the invasive characteristics of the plant became better known. Plants have naturalized over time with the current U.S. habitat now primarily including disturbed areas, thickets, forest margins, meadows, fields, roadsides, and fencerows in the central and eastern U.S.
Several woody stems/trunks rise up from the base of this shrub, with the largest trunks eventually maturing to as much as 6” in diameter. Trunks/branches have sharp thorns. Autumn olive is often found in dense impenetrable thickets. Arching trunks produce arching branches which often dip to the ground. Bark on older trunks peels in long, thin, narrow strips.
Features of this species include: (a) speckled, often thorny stems which are silvery or golden brown; (b) leathery elliptic leaves (2-3” long) with entire but often wavy margins which are grayish green with distinctive silver scales on the undersides; (c) fragrant, funnel-shaped, 4-petaled, silvery white to dull yellow flowers (each to 1/3” long) which bloom during the period of late April to early June in clusters (1-4 flowered umbels) drooping from the leaf axils; (d) fleshy, abundant, scale-dotted, edible fruits which ripen to a speckled red in early fall (September-October); (e) abundant seeds, many of which are widely disseminated by birds to often distant locations.
Fully ripe fruits are juicy, sweet and tart, and may be eaten fresh off the shrub, dried or cooked (pies, jams or preserves).
The genus name Elaeagnus comes from the Greek words elaia meaning "olive tree" and agnos meaning "chaste" or "pure".
The specific epithet ubellata comes from the Latin word umbellatus meaning "bearing umbels" in reference to the flowers appearing in axillary umbels.
Problems
Japanese beetles and 17 year locusts feed on the leaves.
Uses
Invasive features of this shrub outweigh its ornamental assets. It is illegal to purchase, sell or cultivate this shrub in some areas. Where not illegal, it remains an invasive plant that should not be planted or grown in any residential area (particularly in the central and eastern U.S.) where it is likely to spread.
In areas where it is not considered to be invasive, it can be used as an effective background plant, screen or informal hedge.