Lesser Periwinkle

Today's species is lesser periwinkle or Vinca minor. Here it is in our garden, growing around the base of a cotoneaster tree and spreading slowly across the flowerbed and over the wall. I always thought it must be an introduced species but apparently it is thought to be native in the south of England. It's larger sibling, greater periwinkle (Vinca major no less), is introduced from the Mediterranean. You can tell lesser from greater because the former has short-stalked, more elliptical leaves and the calyx-teeth are smooth, whereas the latter has longer-stalked, more oval leaves and hairy calyx teeth. They are flowering a little earlier than usual, joining the crocuses, daphne, viburnum, hellebores and winter jasmine as the only flowers in the garden at present. We did used to have the odd snowdrop but no sign of any this year.