| Calystegia sepium | |
|---|---|
| Calystegia sepium | |
| Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Solanales |
| Family: | Convolvulaceae |
| Genus: | Calystegia |
| Species: | C. sepium |
| Binomial name | |
| Calystegia sepium | |
| Synonyms | |
|
Convolvulus sepium L. | |

Calystegia sepium or Convolvulus sepium (hedge bindweed) is a species of flowering plant in the family Convolvulaceae. It has a subcosmopolitan distribution throughout temperate regions of the North and South hemispheres.
Calystegia sepium is a perennial herbaceous plant that twines in a counter-clockwise direction to a height of up to 3 m (10 ft). The leaves are arranged alternately on the spiralling stem; they are dull green above and paler below, simple and sagittate (arrowhead shaped), 5–10 cm (2–4 in) long and 3–7 cm (1+1⁄4–2+3⁄4 in) broad.
The flowers are white, sometimes tinged pale pink, produced from late spring to the end of summer (between July and September in northern Europe). The buds are enclosed by large (2 cm (3⁄4 in) long), ovate-lanceolate, green bracteoles with keels and burgundy margins; during anthesis they do not (or scarcely) overlap.: 567 The open flowers are trumpet-shaped, 3–7 centimetres (1+1⁄4–2+3⁄4 in) diameter. After flowering, the fruit develops as an almost spherical capsule, which is hidden by the bracts. It is 1 centimetre (1⁄2 in) in diameter, containing two to four large, dark brown, or black seeds that are shaped like quartered oranges.
The plant thrives in hedges, fields, borders, beside water, on roadsides and woodland edges.
There are several species of Calystegia which occur in similar habitats and can be difficult to distinguish, especially when not in flower. C. sepium, C. silvatica and C. pulchra are sometimes recorded as an aggregate, as "C. sepium agg.", whenever identification is uncertain. The use of this term can sometimes create confusion about which taxon is being discussed.
The best way to separate Calystegia sepium from the other taxa is by the bracteoles, which subtend the flower and wholly or partially encompass the sepals. Calystegia sepium has two rather long, narrow bracteoles which do not touch each other, whereas both large bindweed (Calystegia silvatica) and hairy bindweed (Calystegia × pulchra) have shorter, wider bracteoles which overlap where they meet.
In research published in 2025, the genus Calystegia was found to be nested within the earlier-named genus Convolvulus , and its species are now being merged into that genus; this species thus becomes Convolvulus sepium L.
Eight regional subspecies are accepted:
Calystegia sepium is toxic, containing calystegine alkaloids.
Apart from hedge bindweed, other vernacular names include greater bindweed, bearbind, hedge convolvulus, hooded bindweed, old man's nightcap, wild morning glory, bride's gown, wedlock (referring to the white gown-like flowers and the binding nature of the vine), white witches hat, belle of the ball, devil's guts and hedgebell.