What is Jacaranda?
Jacaranda mimosifolia is a spectacular tree, native to the tropical regions of Bolivia and Argentina. It bears masses of vibrant purple-blue flowers in late-spring and again in autumn, and is a popular street tree and garden specimen in warmer climates. While many people fall in love with Jacaranda tree while on holiday and want to grow it at home, it’s a frost-tender deciduous tree that needs a warm growing environment with a minimum temperature of 5°C. However, the dwarf grafted form, Jacaranda ‘Bonsai Blue’, makes it possible to grow Jacaranda in a pot, so you can grow it outdoors in summer and move it under cover for winter.
An unmistakable and glorious sight when in flower, Jacaranda flowers in spring and early summer, bearing many small flowers in large pyramidal clusters. Individual blooms are 3-5cm long, rich purple-blue with a white throat. Flowers are borne on the bare stems before the leaves, or just as the leaves are emerging. Leaves are bright, mid green, and divided.
Jacaranda mimosifolia reaches a height of 15m and a spread of 10m. The dwarf variety ‘Bonsai Blue’ is much more compact, with a height of 1.5m and spread of 45cm.
How to grow Jacaranda
As the only Jacaranda worth growing in the UK, the dwarf variety ‘Bonsai Blue’ should be grown in a pot of well-drained, peat-free compost, keep under cover over winter in a cool but frost-free environment, and moved outside for the summer if desired. Water minimally, feed during the growing season, and prune and repot annually, in late winter or early spring.
Where to grow Jacaranda
Grow Jacaranda in a conservatory or heated greenhouse over winter, in a well-lit position and with a minimum temperature of 5°C. From late spring to early autumn, Jacaranda can be moved outdoors to a sheltered spot in full sun. Do not grow Jacaranda in your home – it doesn’t make a good house plant.
How to plant Jacaranda
Plant Jacaranda in a pot, two to three sizes larger than the pot you bought it in. Use a soil-based peat-free John Innes no 2 potting compost, with added coarse grit or perlite to ensure sharp drainage.
How to care for Jacaranda
Watering sparingly is the key to success with Jacaranda. While in growth from spring to autumn, water only as required to keep the compost just moist and allow to almost dry out between waterings. Through the winter months, allow the compost to dry out. During the growing season, from mid spring to autumn, feed once every 2-3 weeks with a general liquid fertilizer.
Pot on into the next size up of container, in late winter or early spring, until reaching a maximum pot size of 45cm high and wide. Thereafter, top dress annually in late winter by carefully removing the top several centimetres of compost and replacing with fresh material.
How to propagate Jacaranda
Jacaranda ‘Bonsai Blue’ is produced by professional grafting and cannot be propagated at home.
How to prune Jacaranda
Trim as required to maintain a balanced shape, in early spring. Remove any dead shoots at the same time.
Growing Jacaranda: pests and diseases
Red spider mite may be a problem, especially where the atmosphere is dry. Improving levels of humidity deters this pest, by standing the pot in a pebble and water-filled saucer so the pot is clear of the water. Whitefly may also occur when growing under cover. Biological controls are an effective and environmentally friendly method of dealing with both these pests.