By Gary Wade
University of Georgia
Drought and deer tolerance and a long bloom period are other outstanding qualities of this award-winning plant.
BackgroundPerennial plumbago, also called leadwort, belongs to a group of deciduous perennials and shrubs from eastern Africa and Asia. It's a semiwoody, mat-forming perennial that spreads by rhizomes, or shallow underground stems. It thrives in hardiness zones 5 to 9.
The plant dies back to the ground each year. Then it leafs out late in the spring. So, plant it where it won't get damaged by early spring cultivation.
The late spring green-up makes perennial plumbago an excellent plant for interplanting with spring-flowering bulbs. Its leaves will be emerging just as the foliage of the bulbs is dying back.
When they emerge, the shiny green leaves are up to 2 inches long. They turn bronze-red in the fall.
True-bluePerennial plumbago's medium-blue flowers resemble those of woodland phlox. They emerge in terminal clusters in late summer and continue to emerge until the fall frost. It's an exceptionally long bloom period. Each flower is one-half to three-quarters of an inch across and has five petals.
The plant prefers a sunny site. But it will tolerate some afternoon shade. Once you get it established, it's quite drought-tolerant. Plant it in the spring so you'll be sure to get it established before the summer bloom. The spring planting will enable it to become hardier next winter, too.
Fertilize perennial plumbago lightly in the spring and again in early summer, if you need to encourage more rapid cover. Wait until new leaves emerge to prune out any dead wood from the previous season.
Summer cuttings, spring division, root cuttings and seeds are all common methods used to propagate the plant. And you'll want more of this Georgia Gold Medal winner.
(Gary Wade is a Cooperative Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.)