First, a health warning: periwinkles, especially the kind that appreciate the British climate, can be complete thugs. Just this weekend I spotted a quarter-acre monoculture of Vinca major ‘Alba’ (below) covering a stretch of chalk cliff beneath Charles Dickens’ Bleak House in Broadstairs. The wandering stems formed an undulating green custard, studded with thousands of pure white flowers, smothering even the most rampant of competitors. (The latin word ‘vincire’, from which the name vinca is derived, means ‘bind’.)
Vinca major, which generally produces five-petalled, lilac-blue flowers, has its place …. somewhere around the far fringes of the garden where it can revel in dry shade or rampage down a steep bank. Here the plant’s Southern European heritage comes to the fore, rendering it tolerant of drought and summer heat, as well as deep shade. Vinca major is such a voracious visitor that in some countries it’s become a serious problem plant.
Providing you’re happy to tolerate a little bad behaviour, Vinca major will work hard for you. Named, variegated forms such as ‘Maculata’ (green leaves with gold centres), ‘Variegata’ (green edged with white) and ‘Wojo’s Gem’ (cream with green edges and pink stems, below) will spread light across a dark corner faster than you can say “Stop right there!”. Vincas root where the trailing stems touch the ground, rapidly creating enormous clumps of evergreen vegetation.
Don’t be fooled into thinking Vinca minor (lesser periwinkle) is any more polite than her big sister. Yes, she’s a lower growing plant with more delicate leaves, but her ideas about world domination are equal. There are some lovely cultivars, many with RHS Awards of Garden Merit, including ‘Azurea Flore Pleno’ AGM (sky-blue flowers), ‘Atropurpurea’ AGM (deep reddish-purple), ‘Gertrude Jekyll’ (pure white), ‘Ralph Shugert’ AGM (vivid, deep violet) and ‘Variegata’ AGM (green leaves margined cream with violet-blue flowers, below).
Somewhere in between major and minor comes Vinca difformis (imaginatively dubbed intermediate periwinkle), which is an altogether better behaved plant. It spreads slowly to about 120cm and revels in dry shade where little else will grow. Flowering begins in late summer, when the simple blooms appear white, tinged with blue. This bluishness fades to pure white through the winter, whilst the flowers keep on coming. Vinca difformis is a diamond in the rough and well worth tracking down if you are craving a little winter colour in your garden.
Major, minor or somewhere in between, there’s a vinca out there with designs on your garden. Choose the right location and vincas will do your dirty work; make one false move and your precious plants will be engulfed by a rising tide of glossy green foliage. Don’t say I didn’t warn you!