Jacaranda mimosifolia

Common name: Jakaranda

Other common names: Blue haze tree

Names in non-English languages: Spanish Portuguese

Description

Jakaranda originates from subtropical South America, its natural range extending from northern Argentina to southern Brazil.

It is a spectacular flowering tree up to 15 m (50 ft) in height, though is more typically 5 to 10 m (16 to 33 ft) tall with a slim, straight trunk supporting a wide-branching crown. The bark is grey and fissured.

The leaves are large, up to 50 cm (20 in) long and made up of numerous tiny green leaflets in an intricate, twice-feathered arrangement. They fall off the tree in the dry season to conserve water, leaving the branches bare until the rainy season arrives.

In spring, brilliant lavender-blue bell-shaped flowers bloom in clusters that are in stark contrast with the bare branches. Less common is a variety with white flowers.

The flowers are followed by small disc-shaped, woody seed capsules that become dark brown and dry, and when fully mature split open to release their seed, which are winged for wind dispersal.

Use

It is a widely cultivated ornamental in gardens and landscapes in the subtropics for its spectacular flowering display.

The wood is light- to medium-weight, in the 450 to 700 kgs per cubic meter (28 to 43 lbs per cubic ft) range, and has low natural resistance to rot and decay, making it generally unsuitable for outdoor construction. 

Well-formed logs are sawn into lumber for making boxes and crates or are sliced into sheets of decorative veneer. The small-diameter roundwood is pulped for plywood and particleboard or is cut into lengths for firewood. 

Climate

The tree needs cool, dry conditions prior to flowering for good flowering to occur, with the best flowering displays found in sub-humid to moderately humid subtropical and tropical mid- to high-elevation climates, generally areas with annual lows of 7 to 20 °C, annual highs of 20 to 35 °C, annual rainfall of 600 to 1400 mm and a dry season of 2 to 8 months. Although also cultivated in warmer and wetter climates, flowering is sparse to patchy at best.

Growing

New plants can be started from semi-hardwood cuttings or seed, which remain viable for up to twenty-four months under cold, dry, airtight storage. Trees from cuttings are preferred because they start to bloom at an earlier age.

Performs best on free-draining loam and sand soils of a moderately acid to alkaline nature, generally with a pH of 6.5 to 8.0 and on sites with full to partial sun exposure.

Problem features

It is listed as a serious weed in at least one reference publication and is classed as a weed of agriculture in Australia, due in part to its ability to disperse its seed on the wind over far distances. However, it is assessed as a low weed risk species for Hawaii and Florida, respectively by the Hawaii Pacific Weed Risk Assessment project (HPWRA) and the IFAS Assessment of Non-Native Plants in Florida's Natural Areas.

Over the course of the seasons, the spent leaves, flowers and seed capsules fall to the ground creating litter.

Where it will grow

© All rights reserved Iplantz 2016