Vines add vertical beauty to a garden. Although most vines are desirable, some can viciously choke out other plants with their aggressive behavior.
Let's look at four examples. The first two examples are annual plants, meaning that they germinate new plants from seed each spring and then die each fall.
Morning glory (Ipomoea sp.) is a good example of a beautiful annual vine that can become invasive. Morning glory plants grow two to ten foot in a growing season. Their funnel-shaped flowers are available in many different colors. For many years I planted morning glory vines on the picket fence around my herb garden. As the ornamental flowers faded, they dropped seeds onto the ground below. Unfortunately, I now fight weedy morning glory plants in this garden. Last year morning glory plants completely took over an adjacent daylily bed, covering it with a mass of vines and flowers. Pretty, but not desirable.
Bur cucumber (Sicyos angulatus) is a weedy annual vine in the gourd family. Usually considered weedy because it doesn't have strong ornamental features, and is not edible. It prefers wet locations, and I've seen this plant cover tall trees and shrubs along the Illinois River. Bur cucumber has slender stems and each year climbs to heights over 25 feet using tendrils. The plant spreads by reseeding itself. Its spiny fruit clings to animal fur that helps distribute the seed.
These two annual vines are a nuisance but can be controlled over time by removing the seedlings as they germinate, being sure that the plant doesn't flower and produce more seed. Most of their seeds emerge within two years after the seeds shed, but some seeds can remain viable in the soil for several years.
The next two examples are weedy perennial vines that continue to invade more landscapes and gardens each year. Perennial vines are much more difficult to manage because they move underground in addition to reseeding. Managing these very aggressive plants requires containing or controlling their root system.
Similar to our native American bittersweet (Celastrus scandens), the invasive Oriental bittersweet (Celastrus orbiculatus) vine has brightly colored berries used in crafts and displays. Birds and small animals eat and disperse the seeds of Oriental bittersweet into new locations. Once there, the vine engulfs plants and structures around it, climbing to heights of 60 feet. At the same time, new plants sprout from its roots that creep and spread underground.
Likewise, black swallowwort (Cynanchum louiseae) spreads by seeds and roots. Similar to other plants in the milkweed family, its cottony seeds disperse with the wind. Once established, its dense rhizome roots invade the surrounding landscape and garden. Though in the milkweed family, this plant is not an Asclepias species and thus is not a food source for monarch butterflies.
Rest assured that not all vines are vicious. Learn more about the good climbers and twiners in our University of Illinois Extension Vines website at http://extension.illinois.edu/vines/.