There are just handfuls of alliums that actually prefer shade and, like many plants which grow in these conditions; they are both white in bloom. They include alliums with its loose flower heads and unusual triangular stems. It is often called the three cornered leek. Growing to around 15 inches, it thrives in damp shade but, being a native of southern Europe, is only borderline hardy although it has now naturalized in several parts of the British isles.

Meanwhile, its slightly shorter relation, ursine, is native to wide regions of northern Europe into Russia and is fully hardy. It revels in damp woodland conditions where it can become invasive. It is colloquially known as wild garlic on account of its smell, and like the domesticated garlic, it has many medicinal properties. Its leaves and flowers are used to flavor salads and soups.

These in turn associate well with ornamental grasses. All these plants look striking against blue green slate mulch. An alternative bulb for the gravel garden could be flatus, again only 12 inches high. It has attractively colored blue green leaves and contrasting yellow flowers with up to 60 tiny bells on each stem. It too loves a sunny spot and will self seed easily.

Another choice could be cerulean with its rich blue drumstick type flower heads, only 1 inch across, borne on slender stems in early summer. The leaves die back completely before flowers appear. All three alliums could be planted in close alliance for a late spring and early summer display. Unlike many alliums, foliage is a positive asset in the case of keratin, which grows around 8 inches high.