Buddleja are sometimes called butterfly bushes because they are renown for attracting these insects. Buddleja davidii, of Chinese and Japanese origin, does as well in Sydney gardens as it does in much cooler areas. In late spring and throughout summer, its arching branches bear long, tapering panicles are made up of dense clusters of tiny, fragrant flowers, in colours of white, mauve, deep purple, magenta and pink. They are generally medium to tall shrubs growing to 2-3.5 m. My favourite of the tall cultivars is 'Pink Delight', with mid-pink blooms. There are some interesting variegated-leaf cultivars, such as 'Harlequin', which has cream-margined foliage and purple blooms. There are also smaller-growing cultivars, such as 'White Ball' and the Buzz series, for smaller spaces. The 'Buzz' cultivars, which come in hues of white, deep purple, pink and burgundy, are said to be sterile and thus won't self-seed. They grow taller than was originally expected, however, reaching 1.5 m or more! Plants in a newer series, called 'Lo and Behold' are said to definitely only get to 50 cm. A beautiful weeping form known as 'Wisteria Lane' is said to grow to 1 m and really does look like a miniature wisteria when in bloom.
They do attract butterflies, which feast on the scented nectar and when 'blue triangle' butterflies, with their stunning turquoise-coloured wings are hovering around the flowers, it is an amazing sight! Buddleja davidii flowers best in a sunny, well-drained spot. The shrubs are quite tough once established, and survive dry spells very well. Trim off the deadheads regularly so you get a new flush of flowers. I cut the shrubs back very hard around mid-August, reducing each almost to a stump! New growth will soon emerge and a nice shape will form. Left unpruned, they can become very straggly. They make a good statement in any mixed border, with companions such as Salvia, Abutilon, perennial Aster, Dahlia and Canna.
Cuttings of Buddleja strike fairly easily and late summer and autumn are good times to try them. Note that Buddleja (except for the 'Buzz' cultivars) may self-seed, so make sure they are not planted nearby bush reserves and that you pull out all unwanted seedlings in your garden, so that you don't end up with a forest of Buddleja!