Daily Mail - Daily Mail Weekend Magazine
Best of BUDDIES
Butterflies just adore buddlejas and we should appreciate them too, says Monty Don, for their hardy spirit as well as their heavenly scent
The butterflies are at their busiest in August, jostling and flitting from flower to flower like shoppers in a sale to reach the nectar of late-season blooms – and there is no plant in the late summer garden that attracts them like buddleja.
Buddlejas are much undervalued – perhaps because they are so ubiquitous and grow so freely on waste ground. They make superb cut flowers, and the scent is heavenly, too.
On the face of it, it is a wonder that buddlejas do not become a weed on the scale of Japanese knotweed or brambles, given that they grow so predictably and prolifically. Surely there is no plant in the British Isles that grows so readily and profusely in the unlikeliest of places? Buddleja davidii in particular will colonise ground that is primarily loose stone, like the shingle on the edges of mountain streams in its native Sichuan, in south-west China. They also particularly like lime, hence the predilection for the mortar in brick walls, urban waste ground, stony railway sidings or an untended back yard. They relish the thinnest chalky soil in a garden. The seeds are light and winged, so they are blown large distances in the wind.
B. davidii was introduced to Western gardens in 1870 by French missionary and keen botanist Père Jean Pierre Armand David. He was also the first Westerner to observe the giant panda and sent a dead specimen back to Paris. But B. davidii was very much alive and it thrived. Many Asiatic plants adapt very easily to British conditions and this adaptation contributes as much to their widespread status in English gardens as the exercise of horticultural choice.
There are around 100 recognised species of buddleja and although most come from the East, they are also found in the Americas and Africa. Around 100 years before David, Buddleja globosa was introduced to Britain from South America. B. globosa and also B. alternifolia are unusual in that they flower on the previous year’s growth, whereas late-flowering buddlejas such as B. davidii, B. fallowiana and B. x weyeriana famously need pruning hard each spring as only the new shoots produce flowers.
But it is B. davidii that reigns in our gardens with its court of nectarintoxicated butterflies. The many hybrids of B. davidii do not have as much nectar as the species, so are not so attractive to butterflies, although the white ones like ‘Peace’, ‘White Bouquet’ and ‘White Cloud’ are more nectarrich than the coloured hybrids.
The coloured hybrids have been bred primarily to be more intense in colour. The blue ‘Glasnevin Hybrid’ has quite small, silvery leaves and lavender flowers. ‘Black Knight’ is an intense purple, and ‘Royal Red’ is a purple so iridescent that it is almost magenta.
All buddlejas that flower after June need pruning back hard in March, leaving just a couple of strongly growing leaves below the cut. This will stimulate lots of new growth that produces the flowers. You can train an old shrub to have shape by leaving the thick stems and training back from them, like pollarding a willow, but you need to keep rubbing off leaves as they appear on the lower stems.