To the ancient Greeks and Romans, glossy-leafed, dark green ivy was sacred to the god Dionysus (Bacchus in Rome). The pagan druids reflected on ivy in the Christmas carol, "The Holly and the Ivy," where the plant represents female divinity. This plant clearly had an impact on ancient cultures but did not stop there. The evergreen vines of this invasive species have vastly covered Europe.
Botanically speaking, English ivy plants are evergreen perennials. They are also classified as woody vines. English ivy plants can act as ground covers, spreading horizontally and reaching 8 inches in height. But they are also climbers, due to their aerial rootlets, which allow them to climb to heights of 50 feet or more. They will eventually bear insignificant greenish flowers but are grown primarily for their evergreen leaves. In this regard, they can be classified as foliage plants.
- Botanical Name: Hedera helix
- Common Name: English ivy, common ivy, European ivy
- Plant Type: Perennial, evergreen climbing vine
- Mature Size: Reaches 6 to 8 inches tall and can spread 15 feet or more
- Sun Exposure: Partial to full shade
- Soil Type: Fertile and moist
- Soil pH: Neutral to slightly alkaline
- Bloom Time: Fall
- Flower Color: Greenish-white, greenish-yellow
- Hardiness Zones: 4 to 9
- Native Area: Europe, Scandinavia, and Russia
The fact that English ivy plants spread quickly means that they could be useful as ground covers for filling in hard-to-plant spots in your landscaping. Their aggressive nature suggests that they could be effective allies against erosion on hillsides. At home indoors or out, English ivy does well planted in containers or baskets where its trailing vines can hang down. Ivy will need protection from winter winds as well as the hot summer sun, so plant appropriately.
English ivy plants grow well in part shade to full shade. Their ability to grow in shade has made English ivy a traditional ground cover for planting under trees. Such areas in your landscaping can be extremely problematic, as most grasses will not grow well there. Vigorous, with a dense growth habit, this ground cover can be effective where the object is to crowd out weeds.
Grow these evergreen vines in well-drained soil. Although it will grow in poor soils and soils of a wide range of pH levels, it does best in average loams.
When watering your ivy, always check the soil before adding water. Ivies prefer to be kept slightly on the dry side, so let the soil dry out some (dry to the touch on top) before you water your ivy plant again. Also, make sure that your plant has excellent drainage. Ivy should not be kept in standing water or overly wet soil.
You can grow the plants in USDA plant hardiness zones 4 to 9. English Ivy plants can grow in temperatures between 45 to 80 degrees Fahrenheit, but they do prefer a consistent temperature and medium to high humidity to keep up its dark green leaves.
Feed English ivy every two weeks during the spring and summer season with half the recommended dose of basic houseplant food. Fertilize monthly in the fall and winter. Do not use fertilizer or plant food if the plant is in a stressful situation: very hot, very cold, very dry soil, or leaf production that has stopped.
Potting and Propagating
Some homeowners grow these plants in hanging baskets, letting them cascade over the sides. Indeed, considering their invasive quality, the latter is a very sensible way in which to grow the vines for their beauty without having to worry that they will spread out of control.
Repot small ivy plants every year into fresh potting soil, or every other year for larger plants. Old, tired plants can be refreshed and planted back into their same containers.
Ivies propagate readily from stem cuttings. Because they are trailing plants, ivies benefit from trimming—use these trimmings to propagate your plants. Take cuttings 4 to 5 inches long and place them in water until a good network of root hairs has developed, then plant in potting soil.
These vines are poisonous plants for humans, dogs, cats, and livestock. Certain types of ivy plants contain triterpenoid saponins and polyacetylene compounds. When ingested, the irritant within the plant can cause excessive drooling, vomiting, and diarrhea.
Some take advantage of the climbing ability of these vines to use them to cover a wall, trellis, or pergola. They can scale a wall by means of holdfasts, which are aerial-root-like structures. As you can well imagine with a name like "holdfasts," this feature has the potential to result in damage to a wall when removing the vines from it. Growing such vines on walls may or may not be a good idea, depending on the composition of the wall and your ability (and willingness) to repair the wall as needed.
Their holdfasts also allow them to grow on trees. Homeowners often wonder if English ivy can harm trees. The fact is that any vigorous vine can hurt a tree because the leaves of a vine growing in a tree's canopy will block sunlight that would otherwise be used by the tree's leaves in photosynthesis. The added weight from vines is also an unnecessary burden on any tree with stability issues.
The damage they cause to trees and to walls is not the only reason that H. helix vines have fallen out of favor in many circles in North America. As is often the case, aggressive growth is a double-edged sword, allowing you to cover bare spots quickly but at the price of invasiveness. They are considered particularly invasive in the Pacific Northwest.
If English ivy is already climbing one of your trees and you wish to remove it, be careful. Do not just rip a vine off, which could hurt the tree's bark. Instead, cut each vine where you find it coming out of the soil at the base of the tree, where it begins its ascent. Cut off from the earth (and thus from a water source), the part of the vine left anchored in the tree bark will eventually wither and die.
This removal technique is the best way to get rid of the plant organically, but it does require some patience. You will need to go back year after year and cut new growth until, finally, all strength has been sapped out of the plant. It is only at this point that new shoots will stop emerging every spring.
Several cultivars with variegated leaves are available, including Variegata, Caecelia, and Glacier.