Introduction
Soft, delicate, fernlike, deciduous foliage and dense terminal clusters of lavender-blue, lightly fragrant, trumpet-shaped flowers make this large, spreading tree an outstanding specimen planting. The striking blooms can appear any time from April through August (most often May), and are sometimes present before the fresh, new, light green leaves appear in spring. Flowering is reportedly best following a winter with several nights in the upper 30's. Jacaranda may flower best when grown in poor soil. Jacarandas can reach 25 to 40 feet in height with an equal or greater spread, and the bent or arching trunks are covered with light brown bark.
General Information
Scientific name: Jacaranda mimosifolia
Pronunciation: jack-uh-RAN-duh mih-moe-sih-FOLE-ee-uh
Common name(s): jacaranda
Family: Bignoniaceae
USDA hardiness zones: 9B through 11 (Figure 2)
Origin: native to southern and central South America
UF/IFAS Invasive Assessment Status: not considered a problem species at this time, may be recommended (North, Central, South)
Uses: parking lot island 100-200 sq ft; parking lot island > 200 sq ft; street without sidewalk; tree lawn > 6 ft wide; shade; specimen
Description
Height: 25 to 40 feet
Spread: 45 to 60 feet
Crown uniformity: irregular
Crown shape: vase, spreading
Crown density: open
Growth rate: fast
Texture: fine
Foliage
Leaf arrangement: alternate
Leaf type: bipinnately compound, odd-pinnately compound; made up of 20 secondary leaflets per primary leaflet
Leaf margin: entire
Leaf shape: obovate, rhomboid
Leaf venation: unknown
Leaf type and persistence: deciduous
Leaf blade length: 9 to 18 inches; primary leaflets are 5 inches; secondary leaflets are ¼ inch
Leaf color: green
Fall color: no color change
Fall characteristic: not showy
Flower
Flower color: lavender to violet purple
Flower characteristics: very showy; lightly fragrant; emerges on numerous 12-18" long panicles
Flowering: spring and summer
Fruit
Fruit shape: round, disk-like capsule
Fruit length: 3 inches
Fruit covering: dry or hard
Fruit color: brown
Fruit characteristics: does not attract wildlife; not showy; fruit/leaves a litter problem
Trunk and Branches
Trunk/branches: branches droop; showy; typically one trunk; no thorns
Bark: light brown, smooth, becoming blocky and rough with age
Pruning requirement: needed for strong structure
Breakage: susceptible to breakage
Current year twig color: gray, brown
Current year twig thickness: thick
Wood specific gravity: unknown
Culture
Light requirement: full sun
Soil tolerances: sand; loam; clay; slightly alkaline; acidic; well-drained
Drought tolerance: high
Aerosol salt tolerance: none
Other
Roots: can form large surface roots
Winter interest: no
Outstanding tree: no
Ozone sensitivity: unknown
Verticillium wilt susceptibility: unknown
Pest resistance: resistant to pests/diseases
Use and Management
The light, dappled shade makes jacaranda well-suited for cooling patios, but it probably should not be used near pools due to the abundant leaf and flower drop. Jacaranda makes an ideal street tree, creating a spectacular sight when in full bloom. The arching branch habit is ideal for creating a canopy over a street or boulevard. Be sure to plant only those trees which have one central trunk and major limbs well-spaced apart for street tree and other high-use areas. Unpruned trees can become hazardous as they split apart at the crotches. Once properly trained and pruned, jacaranda is fairly strong-wooded and less messy than royal poinciana.
Heaviest-flowering when grown in full sun, small trees of jacaranda can tolerate light shade and will grow quickly. They thrive in sandy, well-drained soils but should be watered during dry periods. Prune branches so they remain less than half the diameter of the trunk to help keep the plant intact and increase durability.
'Alba' is a white-flowered cultivar which has a longer blooming period but sparser blooms. There are other cultivars available.
Propagation is by softwood cuttings, grafting, or by seed. Seedlings often take a long time to bloom so grafted trees or those rooted from cuttings are preferred.
Pests
No pests are of major concern.
Diseases
Mushroom root rot is a problem on poorly-drained soil.
Reference
Koeser, A. K., Hasing, G., Friedman, M. H., and Irving, R. B. 2015. Trees: North & Central Florida. University of Florida Institute of Food and Agricultural Sciences.