How to identify bindweed vs morning glory
Bindweed and morning glory are both twining vines with funnel-shaped flowers that look nearly identical from a few feet away. The practical difference is enormous: morning glory is an annual that dies with frost and is easily managed; field bindweed is a deep-rooted perennial weed rated as one of.
—- title: "How to identify bindweed vs morning glory" slug: how-to-identify-bindweed hub: problems category: "Identification guide" description: "Tell field bindweed and hedge bindweed from ornamental morning glory by leaf shape, flower size, and root depth. Bindweed is a deep-rooted perennial; morning glory is an annual." date: 2026-06-10 updated: 2026-06-10 author: "Thomas A." reading_time: 8 —-
Bindweed and morning glory are both twining vines with funnel-shaped flowers that look nearly identical from a few feet away. The practical difference is enormous: morning glory is an annual that dies with frost and is easily managed; field bindweed is a deep-rooted perennial weed rated as one of the 10 worst agricultural weeds in the world.
Field bindweed (Convolvulus arvensis)
What field bindweed is
Convolvulus arvensis is a native European vine introduced to North America in the early 1700s and now present in all 50 states. Per UC IPM, it is one of the most difficult-to-control agricultural weeds because its root system extends 10–20 feet deep, with lateral roots spreading 15+ feet. No practical management eradicates the root system in a single season.
Identification
Leaves: Arrowhead-shaped (hastate) with two backward-pointing basal lobes (auricles). Per UC IPM, the leaf is typically 1–2.5 inches, longer than wide, with two distinct ear-like lobes at the base where the petiole meets the blade. This arrowhead leaf shape is the fastest field ID.
Stems: Twining, smooth, 1–3 feet long, creeping along the ground or climbing any available support.
Flowers: Funnel-shaped, 0.75–1.5 inches across, white to pale pink with faint stripes. The small flower size is a helpful separator from hedge bindweed's larger flowers and morning glory's much larger flowers. Per Penn State Extension, flowers open in morning and close in afternoon.
Root: A deep, fleshy taproot and a network of horizontal roots that can regenerate from fragments as small as 2 inches. Per UC IPM, every piece of root cut during cultivation becomes a potential new plant.
Hedge bindweed (Calystegia sepium)
A closely related native species, often confused with field bindweed. Per Penn State Extension, the primary differences:
- Larger flowers: 2–3 inches across (vs. 0.75–1.5 inches for field bindweed)
- Larger leaves: 2–4 inches, similar arrowhead shape but larger
- Two large bracts at the base of the flower that nearly hide the sepals — visible when you look at the flower from the back
- More aggressive climbing habit: Hedge bindweed climbs higher and more vigorously than field bindweed
Both are perennial weeds. Per Penn State Extension, hedge bindweed is the more commonly encountered roadside species in the Northeast; field bindweed is more prevalent in cultivated fields and gardens.
Morning glory (Ipomoea purpurea and related species)
What morning glory is
Per NC State Extension, ornamental morning glories are annual vines that die at frost. They are native to tropical America and are widely grown for their large, showy flowers.
Identification features
Leaves: Heart-shaped (cordate), without the arrowhead basal lobes of bindweed. The base curves smoothly around the petiole — no pointed ear lobes. Per NC State Extension, leaves are 3–5 inches, much larger than field bindweed leaves.
Flowers: Funnel-shaped, 2–4 inches across — noticeably larger than field bindweed. Colors range from purple, blue, red, pink, and white, depending on cultivar. Per NC State Extension, the variety of flower colors in cultivated forms is a quick separator from field bindweed (white/pale pink only).
Annual habit: Dies at first frost, leaving no persistent root system. New plants each year from seed.
Hairiness: Morning glory stems and leaves are often hairy to lightly hairy. Field bindweed is nearly smooth.
Sweet potato vine (Ipomoea batatas)
Related to morning glory, sometimes confused with bindweed in ornamental beds. Per NC State Extension, sweet potato vine is a non-climbing sprawling annual with deeply lobed to heart-shaped leaves in various colors (green, purple, bronze). It does not twine around supports.
Comparison table
| Feature | Field bindweed | Hedge bindweed | Morning glory |
|---|---|---|---|
| Leaf shape | Arrowhead with basal lobes | Arrowhead, larger | Heart-shaped, no lobes |
| Leaf size | 1–2.5 in | 2–4 in | 3–5 in |
| Flower size | 0.75–1.5 in | 2–3 in | 2–4 in |
| Flower color | White or pale pink | White to pale pink | Purple, blue, red, pink, white |
| Bracts at flower base | Small | Two large bracts | None/small |
| Annual or perennial | Deep perennial | Perennial | Annual |
| Root depth | 10–20 ft | 6–10 ft | Shallow annual |
Management of bindweed
Per UC IPM, the reality of field bindweed management:
No single-season eradication: The deep root system means repeated, sustained management is required. Per UC IPM, complete eradication of an established stand typically takes 3–5 years of consistent effort.
Cultivation (pros and cons): Tilling depletes root reserves when done repeatedly, but also chops roots into fragments that sprout new plants if cultivation is infrequent. Per UC IPM, cultivation must be done every 2–3 weeks throughout the growing season to be effective.
Herbicides: Per Penn State Extension, glyphosate applied when the plant is actively growing and flowering is most effective. The plant is moving carbohydrates to roots at this stage, pulling herbicide down with them. Repeat applications for 2–3 seasons are necessary.
Smothering: Dense mulch (6+ inches) or light-blocking tarps suppress bindweed for a season, but the deep roots persist and re-emerge when light is restored.
Frequently asked questions
My annual morning glory self-seeded and came back this year. Does that make it a perennial? No. Per NC State Extension, Ipomoea purpurea is strictly annual. Self-seeding is vigorous in warm climates (zones 7+), and the plants that emerge from self-sown seed look like they returned — but they are new plants from seed, not regrowth from a root system. If you want to control it, prevent seeding.
Is there a useful biological control for bindweed? Per UC IPM, two biological control agents are approved and released in the western US: bindweed gall mite (Aceria malherbae) and bindweed moth (Tyta luctuosa). Their impact in field settings has been variable. They do not eliminate bindweed but can reduce its density over time in combination with other management practices.
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Sources:
- UC IPM — Field bindweed
- Penn State Extension — Field bindweed
- Penn State Extension — Hedge bindweed
- NC State Extension — Ipomoea purpurea