Euphorbia (Blackbird) An evergreen perennial with purply black foliage which gives the plant its name. The feather-like leaves are darkest when young, but remain dark enough to act as the perfectly contrasting foil to the reddish stems and pale green foliage. The flowers (which are, technically, bracts) appear in late January but even without them the plant is interestingly bird-like all year round. It needs full sun and a well-drained soil, and makes a good, dense clump 60cm high and wide.