Buddleja davidii 'Black Knight' (Butterfly Bush) - 2 Gallon Potted ShrubBuddleja davidii 'Black Knight' (Butterfly Bush) is a vigorous large deciduous shrub with gracefully arching branches, studded with lance shaped, dark green leaves with white felted undersides, and sweetly scented, elongated panicles of dark purple, almost black flowers. Borne at the tips of current year's growth, the long flower spikes, up to 10 in. (25 cm), are on display from mid summer through early fall and sometimes to first frost. A superb,