Learn about a few key invasive plants impacting horticulture, including Baby's Breath; Butterfly Bush; English Ivy; and Himalayan Blackberry. Please help prevent (alert species): Common Morning Glory and Tree of Heaven. For distribution of these and other invasive plants impacting horticulture in BC, please refer to the Grow Me Instead booklet.
Baby’s Breath (Gypsophilia paniculata)
Beautiful herbaceous perennial with delicate white or pink blooms on a bushy flower stalk which makes it sought after by garden enthusiasts and florists alike. That said, it is very drought tolerant in hot, dry climates such as the Okanagan. The large tap root can extend to 4m and rob other plants of minerals, nutrients, space and water thus outcompetes with other plants. The roots are allopathic and the entire plant is not palatable to most livestock. An average plant produces ~ 13,700 seeds which spread easily as the plant stalk naturally breaks off sending the plant tumbling across the landscape. Given time the plant can quickly become a difficult to control monoculture.
ALTERNATIVES: Pearly Everlasting, Filigran Russian Sage, Hewitt’s Double Meadow Rue, Sea lavender, White Flax, Hybrid Yarrow, and German Statice.
Butterfly Bush (Buddleia Davidii)
A known invasive in the Lower Mainland where the climate and growing conditions allow for rapid spread of this plant along riparian corridors, open and disturbed areas and along coastal forest edges, and roadsides. This plant has recently escaped cultivation and spreads by large amounts of windborne seed. Once established this plant displaces native vegetation, supplants other plants as a nectar source thus reducing their pollination and outcompetes native vegetation.
ALTERNATIVES: Lewis’s Mock Orange, Red-Flowering Current, Black Chockberry, Meyer Lilac, California Lilac, Blue Elderberry, Weigela, Rose of Sharon, and Oceanspray.
English Ivy (Hedera helix)
A plant commonly used for ground and building/wall covers that quickly smothers other plants and robs them of light, space, nutrients and minerals. Invasive in much of SW BC, the plant assumes two types of complex root growing habits: horizontal and vertical, the latter being its reproductively mature state which can quickly overtake and debilitate or choke out trees and infrastructure. The plant also produces a large volume of seed which is eaten and widely distributed by a number of wildlife species.
ALTERNATIVES: Salal, Deer Fern, Purple Wintercreeper Euonymus, Taiwan Creeping Raspberry, Privet Honeysuckle, Boston Ivy, Barrenwort, western honeysuckle, and the piggy-back plant.
Himalayan Blackberry (Rubus armeniacus)
Highly valued for its delicious and numerous berries and for its ability to act as a security measure on properties, this plant quickly takes over many habitats. It out-competes with low growing native vegetation and prevents their re-establishment. Plants can grow to 5 m in height with canes reaching up to 12 feet in length that root wherever they touch the ground and create impenetrable thickets for people and wildlife.
ALTERNATIVES: Nootka Rose, Thimbleberry, Marionberry or Boysenberry, Red Raspberry, Black Huckleberry, Black Raspberry, Salmonberry, Blueberry, and other berries.
Please Prevent (alert species):
Common Morning Glory (Calystegia sepium)
A herbaceous perennial, this plant is a species of bindweed that rapidly and effectively twines around other plants, in a counter-clockwise direction, to a height of up to 2–4 m. Because of its quick growth, clinging vines and broad leaves, it can overwhelm and pull down cultivated plants including shrubs and small trees. Due to its aggressive self-seeding (seeds can remain viable as long as 30 years) and the success of its creeping roots (they can be as long as 3–4 m) the plant is a persistent weed.
Tree of Heaven (Ailanthus altissima)
This tree grows quickly (capable of reaching heights of 15 metres (49 ft) in 25 years), develops many suckers and emits a foul smelling odor. It can rapidly colonise disturbed areas and suppress competition with allelopathic chemicals. When cut, the tree resprouts vigorously thus making its eradication very difficult, costly and time consuming.