Pretty Flowers, Noxious Invaders: Bindweed

The weather these September days has been glorious. The air is dry, the temps in the 70s, the sun shining happily. Perfect weather for a bike ride on one of our favorite trails. Along the way we stopped a few times to inspect some of the foliage growing along the trail. Amid the various shades of green, white, two-inch-long bell-shaped flowers popped. They were blooming on long, vining stems that were climbing the upright stalks of nearby plants. The flowers were accompanied by large smooth leaves with pointed tips and square wings at the base. They turned out to be the flowers of hedge bindweed (Calystegia sepium) a member of the morning glory family. And when we got home, sure enough, there they were, growing in our fence row as well.

In spite of its pretty flowers, hedge bindweed is not welcome in gardens and fields. It is termed a noxious weed, and has other names like great bindweed, devil’s vine, lady’s nightcap, and wild morningglory. Hedge bindweed is a perennial plant native to the Eastern United States. It has managed to spread across the prairie. It can grow up to ten feet long, and it’s called bindweed because it will climb up and cover whatever it can reach, winding itself around its neighbors and creating a mass of foliage that can take over a garden, a fence row, or a field.

Hedge bindweed propagates through rhizomes that send up shoots as they creep along the ground in early spring. As the shoots grow into vines, they hunt in a counterclockwise direction until they find a suitable support. When they do, they wind their way around the support plant until they reach the top where the most sunlight is available.

Later in the spring, the seeds which the plant dropped last fall will begin to germinate, adding more bindweed to the mix. Between these two approaches, hedge bindweed spreads aggressively and is very hard to get rid of. The seeds can lie dormant in the soil for literally decades, and a piece of the root system buried deep in the soil can send up new shoots. It’s no wonder farmers and gardeners are not in love with this pretty plant.

Another name for this plant is hedge false bindweed because, annoying as this plant is, it’s not as bad as its cousin field bindweed.  

Field bindweed, (Convolvulus arvensis), is another member of the morningglory family. It is not native to North America. Also known as field morningglory, creeping Jenny, and devil’s guts, it was first documented in Virginia in 1739. It is native to Europe and Asia, but for the past 300 years has been colonizing North America from the Atlantic to the Rockies and beyond. Its flowers are smaller than the hedge bindweed flowers, and its leaves are also smaller without the telltale lobes at the base. The vines grow over ten feet long and wrap around everything in its vicinity. If it can’t find something to climb on, field bindweed will form dense mats of foliage on the ground. It is hard to get rid of because of its extensive root system and prolific seeds. It spreads aggressively, with one plant’s root system able to cover ten to 18 feet horizontally and 20 feet deep in a single season. One plant can produce up to 600 seeds, and those seeds can remain viable in the soil for 40 years or more. Not only that, but the seeds survive intact when birds eat them, and then deposit them far from the mother plant. Field bindweed can reduce crop production by as much as 50% because it robs the crops of needed water.

I learned as a farmer’s daughter that morningglory was bad, and I wondered how something with such a beautiful name could be so despised. I guess this is why.

Photo by Author. Alt text: Snow-white, trumpet-shaped, 5-petaled blossom of Hedge Bindweed shines forth from atop a tangle of foliage.  In this case, the invasive has climbed up a hemp plant, aka “Iowa Ditchweed,” to get the view from on high.