Linum lewisii (aka Linum perenna); perennial Blue Flax.

This is my favorite blue in the garden, and it is at its best here in
May before most other stuff has opened. I started this stand from seed
a couple of years ago, and it is now starting to expand itself
naturally. Although most sites claim "full sun", this location is no
better than part-sun, and it seems to be happy enough with that.

Canon 1DmkIII; EF16-35mm F2.8L; 21mm; ISO-200; f11; 1/80-sec