Callistemon citrinus “Jeffersii” had just started blooming when I took this picture and now it’s in full bloom, so it’s pretty spectacular.
An Australian member of the myrtle family (myrtleaceae?) that gets only 4 to 6ft. tall. A reliable dwarf, you shouldn’t see it revert to anything particularly taller. Hardy down to the low 20s, and very drought tolerant.
Less commonly known as Melaleuca citrinus, the botanists have been busy trying to change the names yet again.