Convolvulus

(Ipomoea indica) A twining perennial vine, Convolvulus is a garden escapee that is capable of completely smothering trees and shrubs. Its trumpet-shaped flowers are brilliant blue with a paler purple-pink inner tube and are produced almost all year, while its leaves are large and tri-lobed. Seeds may be produced under ideal conditions, but its usual method of spread is by broken stem sections taking root or by the dumping of garden waste.