Common Name: ceratostigma
Type: Broadleaf evergreen
Family: Plumbaginaceae
Native Range: Horn of Africa, Kenya, Sudan
Zone: 9 to 10
Height: 2.00 to 3.00 feet
Spread: 1.00 to 2.00 feet
Bloom Time: July to August
Bloom Description: Blue
Sun: Full sun
Water: Medium
Maintenance: Low
Suggested Use: Hedge
Flower: Showy
Leaf: Evergreen
Other: Winter Interest
Culture
Winter hardy to USDA Zones 9-10 wherein it is easily grown in average to moderately fertile, humus-rich, consistently moist, gritty to sandy well-drained soils in full sun.
Noteworthy Characteristics
Ceratostigma abyssinicum, commonly called leadwort, is a small tender shrub that typically grows to 3’ tall and to 2’ wide. It is native to eastern and northeastern Africa in Eritrea, Ethiopia, Sudan and Kenya. It is particularly noted for producing a prolific summer bloom of tubular, 5-lobed, phlox-like, intense sky blue flowers (each to 1 1/4”) in clusters on stems clad with leathery, spiny-tipped, bristly to hairy margined, narrow-obovate to elliptic, medium green leaves (to 2 1/2” long) which are pubescent on both sides. Evergreen leaves acquire bronze-red tones in autumn.
C. abyssinicum is a frost intolerant plant that has the least amount of winter hardiness of the five species in the genus Ceratostigma that are grown in gardens.
Genus name comes from the Greek words keras meaning a horn and stigma from the hornlike projection on the stigma of the flower.
Specific epithet means native to Ethiopia (Abyssinia).
Problems
No serious insect or disease problems.
Uses
South of USDA Zone 9, this shrubby plant must be grown in containers that are overwintered indoors in a sunny window. Performs well in conservatories or cool greenhouses.