summer to frost
18 to 24 in.
12 to 18 in.
known only in cultivation
USDA zones 4-9
hardy to 8,000 ft.
Sunny border blue speedwell is a perennial flower that grows as a tidy clump of dark green, coarse, wrinkled leaves. In early summer, the deep-blue flowers are densely arranged on upright terminal spikes. It will rebloom if the stalks of spent flowers are cut off.
Sunny border blue veronica has been a great perennial flower at the Xeriscape Demonstration Garden. Although not quite as showy as blue salvia, it is a very dependable plant that seems to hardly be affected by Colorado's erratic weather. It has attractive blue flowers and a nice, upright shape.
Cut back the stalks of spent flowers to a set of healthy leaves to encourage rebloom. Cut old stems and leaves to ground level in late winter.