Erigeron glaucus

Glaucous-leaved fleabane or beach aster from the west coast of USA, from Oregon to California. It thrives in coastal bluffs and sand dunes. It prefers sandy or well-draining soil, full sun, and is highly tolerant of salty sea spray and coastal winds. So this is the one to choose, not the similar looking Aster alpinus, for a warmer climate or if you want lots and lots of flowering!

A clump-forming perennial bearing flowers with a yellow eye and mauve petals in summer. Grey-green, lance-shaped leaves. Grows to 20cm high and has a spread of 30cm. 

Sadly only a small plant image or one that has been over a year in this spot, a bit hard, dry, small and facing north in a small trough. Taken in mid June.

AI says: While they look very similar, Erigeron glaucus (Seaside Daisy/Beach Aster) and Aster alpinus (Alpine Aster) differ in habitat, bloom time, and floral structure. Erigeron is a coastal, long-blooming groundcover with flat bracts, (te small modified leaves behind the collection of individual florets,  known as phyllaries, they protect the developing flower buds and help identify different aster species).. In comparison Aster alpinus is a true alpine, short-blooming clumper with layered bracts.  (The last image shows a different alpine aster species)