Lithodora is a hardy evergreen creeping groundcover originating in southern Europe requiring only a little attention. It can hug the ground very closely or mound upward to six inches or rarely as high as a foot.
It spreads as a dark green mat that produces its first few bright azure blue flowers as early as March, but is really going to town blooming in May and June, continuing to bloom at intervals less overtly up to Autumn's first frost. In mild weather, it will even produce the occasional bloom, one or two bright blue spots at a time, in any month of the winter.
It likes a little acidity in the soil, but isn't fussy. It likes lots of sun but will tolerate shade. It is very cold-hardy but prefers temperate weather won't often thrive in American South or Southwest climates. It does not want much moistness can even survive in droughty conditions under conifers, though blooms will be fewer without sun. It is ideal for rockery ledges, which is where we've planted ours.
Each plant will quickly spread to two feet, in the longer run could conceivably spread to six feet, though so easily pruned to size there's no risk of it becoming aggressive. When it stops blooming, for the most part in early autumn, that's the time to trim it every other year or so, to keep it from getting too spindly to encourage regrowth at the center.