Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, Andrew K. Koeser, Deborah R. Hilbert, and Drew C. McLean
Introduction
This many-branched, broad, spreading, flat-crowned deciduous tree is well-known for its brilliant display of red-orange bloom, literally covering the tree tops from May to July. There is nothing like a royal Ppoinciana (or better yet, a group of them) in full bloom. The fine, soft, delicate leaflets afford dappled shade during the remainder of the growing season, making royal poinciana a favorite shade tree or freestanding specimens in large, open lawns. The tree is often broader than tall, growing about 40 feet high and 60 feet wide. Trunks can become as large as 50 inches or more in diameter. One to two-feet-long, dark brown seed pods hang on the tree throughout the winter, then fall on the ground in spring creating a nuisance.
Figure 1. Full Form—Delonix regia: royal poinciana
General Information
Scientific name: Delonix regia
Pronunciation: dee-LOE-nicks REE-jee-uh
Common name(s): royal poinciana
Family: Fabaceae
USDA hardiness zones: 10B through 11 (Figure 2)
Origin: native to Madagascar
UF/IFAS Invasive Assessment Status: caution, may be recommended but manage to prevent escape (South); not considered a problem species at this time, may be recommended (North, Central)
Uses: street without sidewalk; specimen; shade; reclamation; urban tolerant
Figure 2. Range
Description
Height: 35 to 40 feet
Spread: 40 to 60 feet
Crown uniformity: symmetrical
Crown shape: vase, spreading
Crown density: moderate
Growth rate: fast
Texture: fine
Foliage
Leaf arrangement: alternate
Leaf type: bipinnately compound; made up of 10 to 20 pairs of primary leaflets and each are made up of 25 to 35 pairs of secondary leaflets
Leaf margin: entire
Leaf shape: oblong
Leaf venation: unknown
Leaf type and persistence: semi-evergreen
Leaf blade length: 8 to 20 inches; leaflets are ½ inch
Leaf color: green
Fall color: no color change
Fall characteristic: not showy
Figure 3. Leaf—Delonix regia: royal poinciana
Flower
Flower color: brightred or orange
Flower characteristics: very showy; emerges in clusters at the ends of branches
Flowering: spring to early fall
Figure 4. Flower—Delonix regia: royal poinciana Credit: Korhnak
Fruit
Fruit shape: elongated, flat, pod or pod-like
Fruit length: 1 to 2 feet
Fruit covering: dry or hard
Fruit color: dark brown
Fruit characteristics: does not attract wildlife; showy; fruit/leaves a litter problem
Fruiting: late summer
Figure 5. Fruit—Delonix regia: royal poinciana Credit: UF/IFAS
Trunk and Branches
Trunk/branches: branches droop; not showy; typically multi-trunked; no thorns
Bark: light brown and smooth, becoming slightly roughened and spotted with age
Pruning requirement: needed for strong structure
Breakage: susceptible to breakage
Current year twig color: green, brown
Current year twig thickness: medium, thick
Wood specific gravity: unknown
Figure 6. Bark—Delonix regia: royal poinciana Credit: Gitta Hasing
Royal poinciana will provide fullest flowering and best growth when planted in full sun locations. Tolerant of a wide variety of soils and conditions, royal poinciana needs to be well-watered until established, then only during the severest droughts. Grass grows poorly beneath poinciana. Do not plant closer than about 10 feet from pavement or sidewalks, since large surface roots often grow beneath them and can destroy them. Early pruning is required to encourage development of branches which are well-attached to the trunk. This will help compensate for the weak wood. Train the tree so the major limbs are located 8 to 12 feet from the ground to allow for adequate clearance beneath the tree. To develop a strong, durable tree, prune major limbs to prevent them from growing to more than half the diameter of the trunk.
Propagation is by seed.
Pests and Diseases
No pests or diseases are of major concern although caterpillars can eat some foliage. There is a root fungus which can kill a weakened tree.
References
Koeser, A. K., Hasing, G., Friedman, M. H., and Irving, R. B. 2015. Trees: North & Central Florida. Gainesville: University of Florida Institute of Food and Agricultural Sciences.
Koeser, A.K., Friedman, M.H., Hasing, G., Finley, H., Schelb, J. 2017. Trees: South Florida and the Keys. Gainesville: University of Florida Institute of Food and Agricultural Sciences.
