x-Buddleja davidii 'Black Knight'
All buddlejas are adored by butterflies, moths and other beneficial insects and you are sure to fall in love with 'Dark Knight' yourself once you have seen it.
The darkest of all the popular davidii cultivars, its rich, sweetly fragrant flowers appear in dense spikes of magnificent deep violet flowers each with a tiny, vibrant orange eye at the centre. Held on attractive, arching stems, their soft, grey-green leaves, which turn a gentle yellow before they fall in the autumn, set off the blooms beautifully.
A large, vigorous, fast growing deciduous shrub it is a perfect back bone to a border and looks just as wonderful within a planting scheme of hot coloured late summer crocosmias, dahlias and hemerocallis as it does amongst paler penstemmons, geraniums and salvias. With its nectar rich flowers it would also make a great addition to a veg plot, planted on the edge to bring helpful pollinators into the area.
Buddleja davidii are not fussy plants but will give you their best show in a sunny spot with well drained, fertile soil. As 'Black Knight' flowers on the current seasons growth prune hard in spring, taking out all the flowering stems to just two or three buds above the main, older, woody framework. This will give plants enough time to produce new growth, mature and flower all in the same year. Follow pruning with a generous mulch of garden compost and a general purpose liquid feed to plants a boost.