Rock Purslane is an incredibly versatile succulent.  The advantages are many, such as the ability to be grown in pots or in the ground, very drought tolerant, seacoast tolerant, long bloom periods, and easy maintenance.  It's also one of the few plants that can be grown beneath Oak trees, as long as it receives some filtered light.  Calandrinia will grow up to about 2.5 feet tall in most conditions with equal spread.  Hardy to about 25 deg. F.  One of our favorites!