Leadwort is a vigorous, evergreen climber which bears a profusion of blue or whitefrom May right through to the end of September. It is a very rewarding plant to grow and fairly easy to bring into flower. Give it plenty of warmth and stand it outside in a sheltered spot during warm summer days.
Many people will recognise Leadwort from holidays in Southern 2 Europe, where its rampant growth covers walls and hedges with clouds of blue. It is grown on all continents except Australasia. It is also known as Cape Leadwort. The genus name, Plumbago, is from the Latin word for lead, ‘plumbum’. One species was reputed to be a cure for lead poisoning.
This fast-growing plant can grow into a large specimen with slender branches of more than 2m (6½ft) in length. The blooms, which look rather like those of Phlox, grow in umbels of up to twenty flowers. Each flower can be as large as 35mm (1½in) across and will last for several days.
There are two species of Leadwort grown as house plants — P. auriculata, the Cape Leadwort, has pale blue flowers with a thin, darker blue line running along the centre of each petal. The variety P. a. ‘Alba’ has white flowers. Plumbago rosea, the Scarlet Leadwort, is a smaller plant with red flowers.
Increase Leadwort by takingin June and July.
Take 8-10cm (3-4in) long cuttings with a ‘heel’. Use firm side shoots which have not flowered.
Insert three or five cuttings round the edge of an 8cm (3in) pot filled with an equal parts mixture of sharp sand or perlite and peat. Cover with a well-ventilated polythene bag and keep at 18°-21°C (65°— 70°F).
Pot up into individualof soil-based when cuttings have rooted.
Training your plant
- Pinch out the growing points of rooted cuttings if you want a small, bushy plant. Also, pot up several cuttings in each pot.
- To grow Leadwort as a climber, don’t stop the cuttings. Plant several together with a wire hoop or cane pyramid for them to climb. Tie in new shoots.
- after flowering as the flowers are produced on new wood.
- Cut back main by about two thirds and trim straggly growth.
Pests And Diseases
attacks can be a problem, especially on plants placed outdoors for the summer.
Treatment: Minor attacks can be controlled by spraying the plant with soapy water. Severe attacks may require a suitable.
Red spider mites may attack when conditions are dry and warm. Treatment: Mist Leadwort regularly with a hand spray and soft water to keep red spider mites at bay. If there is an attack, isolate the plant, spray with an insecticide and enclose the whole plant in a polythene bag for 24 hours. Repeat the complete procedure at intervals as necessary.
Generally trouble-free, given good light and an evenly moist compost. Cut back plants by two thirds after flowering to produce new growth.
- : Repot young plants during early spring using a soil-based compost with the addition of a little gritty sand. Use one size larger until the plants are in 20cm (8in) pots. Then top-dress plants annually in pots this size.
- Water generously during the period of active growth and keep the compost evenly moist during summer. In winter, water sparingly and gradually increase water when new growth appears during spring.
- Feeding: Feed with a liquid fertilizer every 14 days during the growing period. Do not while the plant is resting during winter.
BEST GROWTH ENVIRONMENT
- Light: Place the plant where it receives the brightest possible light. Stand Leadwort outside in a sunny, sheltered spot during summer but bring it indoors before the first frosts are due.
- Temperature: Normal room temperature in summer is fine. Keep the plant cooler during winter, at about 10°C (50°F), but don’t let temperatures fall below 7°C (45°F).
- Buy Leadwort in bloom from May to September at garden centres and nurseries. The white variety is not as readily available as the more usual blue one.
- Buy well-shaped plants with glossy and many buds.
- Leadwort can thrive happily for many years.
- Leadwort blooms from spring right through the summer.
- This attractive, evergreen climber is and appreciates a warm, sunny .