Valued for clusters of intense blue, phloxlike flowers that bloom in summer to late fall, when cool hues are often especially welcome in the garden. (For pale blue-flowered Cape plumbago, see Plumbago auriculata.) Tolerates inconsistent watering. Shrubby species are usually treated like perennials in colder zones; cut them back after bloom and apply a thick mulch.Ceratostigma griffithii
Himalayan native that grows to 2 1/2–3 ft. high and wide, with roundish, deep green leaves. Even light frost will nip back the growth on this plant. Blue, phlox-like flowers appear in fall.
Many-branched plant 6–12 in. high, 1/2 –3 ft. wide. Oblong, 2– 4-in., bright green o...
Evergreen or semievergreen vining shrub from China. Grows to 5 ft. tall. Dark green leaves are divided...
From tropical southern Africa. Spikes to 2 ft. tall; green flowers with purple-edged petals. Attractiv...