Tree Ivy: Good Plant or Harmful Pest?
Understand the crucial distinction behind the name "tree ivy" to determine if you have a welcome garden plant or a vine that requires careful removal.
The term “tree ivy” can refer to two different plants with distinct growth habits. One is a well-behaved houseplant and garden shrub, while the other is a common vine that can affect the trees it climbs. Understanding the difference helps determine if you have a desirable plant or a potential problem.
Identifying Tree Ivy
One type of tree ivy is × Fatshedera lizei, a hybrid created by crossing Fatsia japonica with Hedera helix. It grows as an upright, evergreen shrub, reaching four to six feet tall before its branches may bend. Its large, glossy green leaves are a primary identifier, measuring 10 to 25 centimeters across with five lobes.
This hybrid is sold as a houseplant or garden shrub and requires support to be trained as a vine. The other “tree ivy” is the mature form of Hedera helix, or English ivy. In its juvenile phase, this plant has three-to-five-lobed leaves and a creeping habit. As it matures and climbs vertically, its appearance changes.
Mature Hedera helix develops thick, woody stems that attach to surfaces with aerial rootlets. Its leaves become unlobed, heart-shaped, or broadly triangular. This adult form produces small, greenish-white flowers in the fall, followed by clusters of dark, berry-like fruits. This tree-climbing stage of English ivy is the source of most concerns regarding tree health.
The Impact of Ivy on Trees
When English ivy (Hedera helix) reaches its mature form on a tree, it can cause several problems. The weight of the dense ivy growth is a primary concern. A thick covering of ivy can add thousands of pounds to a tree, stressing its branches and increasing the risk of failure during storms or under snow and ice.
This dense canopy creates a “sail” effect, making the host tree more susceptible to being blown over in high winds. The thick layer of leaves can block sunlight from reaching the tree’s foliage, impeding photosynthesis and causing lower limbs to decline. The ivy’s foliage also shades the trunk and major branches, creating a damp environment that encourages fungal growth and conceals structural issues from view.
On the ground, the ivy’s root system competes with the tree’s roots for water and nutrients. This competition is particularly detrimental to young or stressed trees, stunting their growth or hastening their decline.
Caring for Fatshedera Lizei
Caring for the hybrid shrub × Fatshedera lizei is straightforward, as it thrives in shady conditions. Indoors, it performs best in bright, indirect light. A spot near an east-facing window is ideal, as direct sunlight can scorch its leaves.
When planted outdoors, × Fatshedera lizei prefers a location in part to full shade, such as under larger trees or along protected borders. The plant is adaptable but performs best in well-draining soil that is kept moist but not waterlogged. Allow the top inch of soil to dry out between waterings to prevent root rot.
During the spring and summer growing season, apply a balanced liquid fertilizer every few weeks. Pruning helps maintain a desired shape and encourages a bushier form. This plant also tolerates adverse conditions like air pollution, making it a resilient choice for urban gardens.
How to Remove Ivy from Trees
Removing established English ivy (Hedera helix) from a tree requires patience to avoid harming it. The most effective method is to cut the connection between the roots and the climbing vines. Use sharp loppers or a pruning saw to cut every ivy vine at the base of the tree, creating a gap of several inches between the ground and the upper sections.
Once the vines are cut, the ivy in the tree will wither and die over several weeks or months. Although it is tempting to pull the dead vines off, it is best to leave them. Forcibly ripping the vines away can strip the tree’s bark, creating wounds that expose it to pests and diseases.
After severing the climbing vines, manage the ivy stumps and root system on the ground. Pull or dig out the ivy roots in a wide circle around the tree’s base to prevent regrowth. This may need to be repeated over time, as ivy is persistent.