Native to (or naturalized in) Oregon:
- Evergreen ground cover, 15-20 cm high, and vine. Leaves alternate, simple, juvenile leaves 3-5 lobed, adult leaves on flowering branches ovate to rhombic. Adult plants produce greenish-white flowers in globose umbels. Fruit is berry-like, black.
- Sun to shade, grows best in rich, moist, organic well-drained soil, but tolerates acid and alkaline soil. Requires considerable pruning to keep in bounds.
- Hardy to USDA Zone 4 Native to the Caucasian Mountains. Many cultivars, some much less vigorous than the species.
- Oregon State Univ. campus: southeast of Gilmore.
NOTE: Hedera helix has escaped into natural areas, often by animals dispersing the fruit and seeds, and is a serious threat in many ecosystems. In 2010 the Oregon Department of Agriculture placed English Ivy under noxious weed quarantine (OAR 603-52-1200). This ruling "prohibits the propagation, transport, purchase, or sale of H. helix and H. hibernica [in Oregon], regardless of the variety or cultivar."
Tom Wilkins, owner of Wilkins Nursery in Washington, lists the following guidelines for environmentally aware landscape designers who wish to use English Ivy in the landscape (B&B Vol. 50, No. 9, Sept. 1998, p. 13):
- Do not plant the species (Hedera helix) adjacent to woodland or wetland areas if appropriate maintenance cannot be assured ("appropriate maintenance" means ensuring adequate moisture, trimming along perimeters, and trimming back any upright, mature vines).
- Do not plant the species in small areas adjacent to delicate plantings.
- Keep ivy pruned away from trees or wooden structures which will be damaged by the vines.
- Use smaller-leafed forms (e.g., ‘Needlepoint’, ‘Glacier’, etc.) when using ivy in small scale areas.
- English Ivy is quite drought tolerant. However, plantings that are growing vigorously by ample irrigation are unlikely to form fruiting structures, and pose less of a threat to being spread by birds. Therefore, avoid using ivy where it would be difficult to supply adequate water.