Northcliffe Cactus

I have a fascination with cactus blooms.  I've posted pictures many times of my cactus grove on 11th Avenue.  Taking some cuts from those cactus, I planted the "shoots" up at Northcliffe at the big boulder.  It's taken a few years, but now they bloom nicely.  I just can't believe something from an arid desert environment and covered in spiky needles can produce such beautiful flowers...