Plumbago auriculata, also known as Plumbago or Cape Leadwort, is an evergreen shrub, usually grown as a climber. It can be pruned to grow like a vine over supports or pruned into a compact mounded shrub or left to sprawl with its long, gracefully arching branches. It is grown for its pale blue phlox-like flowers that bloom freely throughout the growing season. A white flowered variety - Plumbago auriculata var. alba - is also available. The cultivar 'Royal Cape' has intense cobalt blue flowers.
It is hardy to zones 8 to 11 and can withstand some frosts. Even if killed to the ground, it will usually recover quickly. It may need to be cut back after winter to keep it tidy, even if this is only done every few years. Excessive growth can be removed at any time of year. Plumbago survives with little watering once established, and is considered moderately drought tolerant. It grows best in a place with full sun and fertile soils with good drainage.
Propagate Plumbago easily from seeds, cuttings and suckers. Sow seeds in spring, at 13-18 Celsius degrees (55-64 F), in seedling trays, using a good seedling mix and cover the seeds lightly. Do not allow them to dry out. Even if it may be easy to grown Plumbago from seeds, plants grown from seeds will usually not flower until the second year. The easiest method of propagation is to remove rooted suckers from the mother plant and replant them. Also you can root semi-ripe cuttings in midsummer with bottom heat.
If you live in a colder area you can grow Plumbago as an annual outside, but bring into a frost-free greenhouse over winter for planting out next spring. When over-wintering as a houseplant, bring it indoors before first fall frost to a bright sunny room. Cut back stems hard in late winter to encourage new growth for the coming season. When over-wintering as a dormant plant, cut the stems back and store the plant in a cool, dry, dark corner of a basement or frost-free garage. For growing under glass, use loam-based potting compost and place the pot in full light. Top-dress or pot on in spring. During the growing season water freely and apply a balanced liquid fertilizer every month. Water sparingly in winter.
