三色牵牛（学名：Ipomoea tricolor），又名天蓝牵牛，为旋花科番薯属一年生植物，是常见的观赏植物。可长达3公尺，原产热带美洲。靠缠绕茎攀缘。叶广椭圆形至心形。花直径可达12.5公分，漏斗状，蓝色，颈部黄色，有时为紫色或红色。与甘薯和旋花近缘。

• 'Wedding Bells'

• 'Wedding Bells'特写

"Mexican Morning Glory" redirects here. This can also refer to the red-flowered I. coccinea.

Ipomoea tricolor (morning glory) is a species of flowering plant in the family Convolvulaceae, native to the New World tropics, and widely cultivated and naturalised elsewhere. It is an herbaceous annual or perennial twining liana growing to 2–4 m (7–13 ft) tall. The leaves are spirally arranged, 3–7 cm long with a 1.5–6 cm long petiole. The flowers are trumpet-shaped, 4–9 cm (2–4 in) in diameter, most commonly blue with a white to golden yellow centre.