Dianthus La Bourboule Alba Dianthus La Bourboule Alba Dianthus La Bourboule Alba AGM Tight grey mats, pure white flowers in early summer. £2.60 Out of stock. Pale grey-green foliage and pure white flowers on neat mounds. We think this is a classy plant in every way - the foliage, the neat habit and, of course, the purest of white flowers in early summer. Compact and slow-growing so perfect for growing in a trough or raised bed but strong enough for growing on the rock garden too. It's a long-lived plant too. About 7cm (3") high. Although it shares the 'La Bourboule' name, this isn't a white version of the pink-flowered 'La Bourboule' - the white one is much tighter and slower growing.