One of the worst weeds to find in your garden, may not look like a weed at all.
Ever look at your garden and discovered an abundance of white-flowered vining plants spreading all over? The flowers and foliage look similar to morning glory, but these blossoms are smaller and the leaves narrower. If you didn’t plant it, you may realize - this pretty thing is a weed. Attractive yes, but field bindweed ( Convolvulus arvensis) is a problem. It may be cultivated in some areas but prohibited in others. It’s not listed as a noxious weed in Nevada, but it is on the invasive weed lists of many surrounding states.
Field bindweed’s been a problem for North American gardeners and farmers since the mid-18 th century. This perennial thrives in climates from temperate through tropical and Mediterranean. It’s drought tolerant and prefers bright sunlight so it’s surprisingly widespread. As long as it gets water, it’ll survive even here in North America’s driest desert. It’s a perennial, so it’ll produce flowers and seeds year after year. The seeds can remain dormant for decades.
Usually, bindweed’s a low growing vine, but it can reach two yards tall with support. On the ground, new plants grow from nodes along the stem, so a single plant generates many more. Its root system’ll grow as deep as 20 feet, if soil conditions permit. Most roots occupy the top 24” of soil. With such deep roots, removing them all is almost impossible. The roots also spread, sending out new plants. As if that weren’t enough, it also has underground horizontal stems with nodes that can produce vigorous plants.
Here’s an unfortunate example of a weed that can establish itself and thrive, with or without human assistance. Since it grows easily with flowers like morning glory, people plant it as a ground cover, in hanging pots, and climbing up trellises. Some believe it’s too pretty to pull out.
If all weeds were ugly, they’d be much easier to control!
When bindweed gets established, few other plants can successfully compete. The name “bindweed” is a clue. It isn’t parasitic, since it creates its own food through photosynthesis. It forms dense mats, which block light from tender young plants. It can become so tangled with other plants that it injures them. And it pulls large amounts of nutrients and water from the soil, weakening your plants.
The only truly effective way to deal with bindweed is prevention.
When installing any new plant in your landscape, examine it closely. Some nuisance weeds appear in pots, but these are easy to remove. Inspect the surface of the potting soil for the small arrow-shaped leaves of bindweed. Should you find them, select another plant.
When purchasing soil, compost or mulch, be sure the source is knowledgeable, selling clean product.
If you get bindweed, remove seedlings as soon as they emerge, remove plants before they flower and remove flowering plants before they set seed.
Once established, eradication’s very difficult. Simply pulling it from the soil, like weeding other plants - only effective for very young seedlings. With older plants, the roots and rhizomes spread throughout the planting bed, so removing a single plant or even a few plants only gives underground structures the opportunity to produce more growth aboveground. Seeds are brownish-beige and ~ 1/6 inch. They’ve survived, dormant in the soil, for over 50 years.
For control, no single method’s completely efficient. You must repeat any strategy many times.
Hoeing the plant vigorously can help manage the weed, if repeated every week.
It thrives in full light, so covering with shade cloth, or thick layer of newspaper or cardboard, topped by several inches of mulch, slows its growth.
Some authorities recommend vigorously roto-tilling the ground to break it up. Unfortunately, the broken pieces of roots may produce more plants.
Common herbicides, along with shade cloth, can help control, but not eliminate it. If you select this option, choose one that moves through the plant, not just burn the leaves that it touches. If you use any pesticide, including any herbicide, read the label carefully. It has information on the safest way to use the product.
Field bindweed is one of the worst weeds in horticulture. It thrives in bright light and can tolerate infertile soils as well as drought. It interferes with the growth and yields of many desirable plants.
To prevent it from becoming established, only purchase soil and soil amendments from reputable sources. Scout the landscape regularly for seedlings and remove them as soon as possible. Place mulch between desirable plants to interfere with bindweed.
No method works immediately. For good control, a gardener needs to be as tenacious as the weed itself.
Dr. Angela O’Callaghan of the University of Nevada Cooperative Extension.