A large shrubby perennial with long stems clothed in mid-green, deeply-veined leaves. The flowers are held in dense clusters at the end of each branchlet, and are the most gorgeous shade of bright blue – hence its name. I have found that this plant looks best when encouraged to lean over at an angle, so that it forms even more side branches, and therefore masses of flowers all along the stems. Another trick is to give it a trim on top as it comes up to flower, encouraging bushier growth. Full sun, sheltered from harsh winds, can be tender in severe frosts. 3m x 1.5m. 1 litre pot.