Plumbago, originating from South Africa, grows 6 to 10 feet tall and 8 to 10 feet wide. This plant grows in a mound but will cascade attractively over a retaining wall if placed in the correct position. In the right regions, plumbago flowers and stays blooming year-round. This plant can overwinter in U.S. Department of Agriculture zones 9 to 11, where the temperature stays above -6.67 degrees Celsius. The hardy plumbago can overwinter down to USDA zone 5 where the temperature stays above --6.67 degrees Celsius.
Plant plumbago in an area with full sun and sandy, slightly acidic, well-drained soil. Dig the planting hole so that the plant resides at the same soil depth as it had in the pot. Space multiple plants 36 to 60 inches apart.
Place a 2- to 3-inch layer of mulch around the plumbago. Water the plant, keeping it lightly moist until it establishes itself. Plumbago is drought tolerant once established and will need little water after its roots are firmly in place and it starts growing on its own.
Apply fertiliser marked 10-10-10 after growth begins the first year and each subsequent year in the spring. This will help the plant remain in bloom for a longer period. If you notice the leaves turning yellow, apply a dose of manganese sulphate at this time as well. Follow the directions on the package for amounts, as each brand will differ.
Prune plumbago in winter to keep it in bounds. As this plant is a fast grower, you will need to do this yearly to keep it looking neat. In cooler regions, this will produce an abundance of flowers when the plant blooms in summer. In warmer regions, you can prune off extraneous growth whenever you wish, although you'll be eliminating blooms in the process during some seasons.
Obtain a young plant from a nursery or propagate plumbago yourself by growing seeds or rooting cuttings.