For an entire year I had this listed as "Bloomin' UBO (Unidentified Blooming Object): Mustard (Brassicaceae), Lepidium (peppergrass) species?" Thank you to Naomi_bot for finally ID'ing it. I uploaded a growth habit shot: www.flickr.com/photos/anitagould/8495623/; see comment there from Naomi.
Lobularia is a genus of four or five species of flowering plants in the family Brassicaceae, closely related to (and formerly often included in) the genus Alyssum.
