Buddleja fallowiana B. Balfour & W.W. Smith

Buddleja fallowiana was collected and introduced into Europe by George Forrest and named by Balfour and Smith in memory of George Fallow, a gardener at Royal Botanic Garden Edinburgh, who died in the First World War (Stuart 2006).

Less hardy than B. davidii, B. fallowiana is similar except for the amount of tomentum (hair) covering the stems, leaves and buds, making the species fairly easy to distinguish. The silvery effect is considered of additional horticultural or aesthetic merit. It is a slower-growing and less vigorous species compared to B.davidii and, except in exceptionally mild areas, deciduous. The flower-panicles closely resemble those of B. davidii and the colour can be white, lilac, pale blue or light purple, all with a yellow-orange eye. The white-flowered ‘Alba’ is quite common in gardens and the horticultural trade, and is also considered the most hardy form. Other collections are grown less often, but the pastel shades of the flowers are generally unremarkable. It requires shelter and a well-drained soil to survive the coldest winters, and is root hardy to about –10ºC. Although the top growth may die back after a harsh winter, the plant will grow back from the base in spring (Stuart).

B. fallowiana is very closely related to B. davidii (Chau 2017), and a number of garden cultivars are hybrids of these two species, for example ‘Lochinch’; ‘West Hill’; ‘Bishop’s Violet’; and ‘Mayford Purple’. These hybrids are sometimes erroneously listed under B. fallowiana and are here discussed separately under B. fallowiana × davidii.