Convolvulus arvensis aka Wild Morning Glory

Convolvulus arvensis is also known as field bindweed. It belongs to Convolvulaceae, the morning glory family. This perennial vine lives for years but sheds its leaves each season. It comes from temperate and subtropical parts of the Old World. Its range includes Europe, Asia and northern Africa, plus Britain and Ireland. It grows in fields, hedges, roadsides, lawns and disturbed ground.

The stems creep over soil or twine around nearby plants. They can form thick mats that crowd out native plants. RHS gives a climbing height of 3.3–4.9 feet [1–1.5 metres]. It lists a spread of 1.6–3.3 feet [0.5–1 metre]. NC State gives a low height of 0.25–0.5 feet [0.08–0.15 metres]. It records a spread of up to 15 feet [4.6 metres]. The green stems feel smooth and have no hairs. Simple leaves grow in turn along each stem. Their grey-green blades range from oblong to the shape of an arrowhead. Light and soil moisture affect leaf shape and size.

White or pale pink flowers open in summer. Each bloom forms a funnel about 0.08 feet [0.025 metres] across. Small green bracts sit below the flowers. Round, light brown seed cases, called capsules, follow the blooms. Each holds two seeds. One plant can make as many as 500 seeds. These can stay alive in soil for 20 years. Roots and rhizomes, or underground stems, also spread the plant. This makes it hard to remove.

Full sun suits it best, though it tolerates partial shade. It grows in chalk, clay, loam and sand. Acid, neutral and alkaline soils all suit it. It accepts moist soil that drains well, poor soil and drought. RHS rates its hardiness H7; NC State lists USDA zones 2–10. It grows fast, and keeping it within bounds takes work. RHS reports few pest or disease problems. It needs no routine pruning, but spread may need control.

Its flowers give it value in wild and wildlife gardens. Past uses include groundcover and hanging baskets. Yet it can soon escape from gardens. NC State reports invasive or noxious status in 35 US states. PFAF notes use to flavour a liqueur but names no plant part. This scant record does not show that it is safe as food. PFAF lists no known hazards. Yet it describes root preparations with a strong laxative effect. It also notes past medicinal uses of leaves and flowers. Stems can serve as short-lived ties, and the plant yields green dye.