Thunbergias are tropical flowers usually from India and South east Asia. The Thunbergia erecta is a native of Africa, now quite at home in Inda. There is a white flowered variety , which flowers profusely. Thunbergia erecta is also known as the King's Mantle, and Bush Clock vine. Its blue flowers with their yellow throats cover the bush in a sunny position. All thunbergias are called clock vines , I wonder why.