Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, Andrew K. Koeser, Deborah R. Hilbert, and Drew C. McLean
Introduction
Calabash is an evergreen tree reaching 10 to 25 feet in height with a broad, irregular crown composed of long, spreading branches clothed in 2- to 7-inch-long dark green leaves, which create moderate shade beneath the tree. Calabash is most outstanding in the landscape for its year-round production of flowers and fruit, both of which are unusual. The 2 ¼-inch-wide flowers are greenish white to greenish yellow with purple streaks, bell-shaped, and appear to emerge directly from the branches. These are followed by the emergence of the large, round fruit, 4 to 12 inches in diameter, with a smooth, hard shell, which hang directly beneath the branches. Fruits are poisonous.
Figure 1. Full Form—Crescentia cujete: Calabash
General Information
Scientific name: Crescentia cujete
Pronunciation: kress-EN-tee-uh koo-JEE-tee
Common name(s): Calabash
Family: Bignoniaceae
USDA hardiness zones: 10B through 11 (Figure 2)
Origin: native to Central and South America
UF/IFAS Invasive Assessment Status: not considered a problem species at this time, may be recommended (North, Central, South)
Uses: specimen; deck or patio; street without sidewalk; tree lawn > 6 ft wide; tree lawn 4–6 feet wide; tree lawn 3–4 feet wide; highway median
Figure 2. Range
Description
Height: 10 to 25 feet
Spread: 20 to 30 feet
Crown uniformity: irregular
Crown shape: spreading, round
Crown density: open
Growth rate: moderate
Texture: medium
Foliage
Leaf arrangement: alternate
Leaf type: simple
Leaf margin: entire
Leaf shape: obovate
Leaf venation: pinnate
Leaf type and persistence: evergreen
Leaf blade length: 2 to 7 inches
Leaf color: dark green and shiny on top, paler green underneath
Fall color: no color change
Fall characteristic: not showy
Figure 3. Leaf—Crescentia cujete: Calabash
Flower
Flower color: greenish white to greenish yellow with purple streaks
Flower characteristics: showy; emerges singly from the trunk and branches; described as having an unpleasantly pungent aroma
Flowering: year-round
Figure 4. Flower—Crescentia cujete: Calabash
Fruit
Fruit shape: round to elliptic
Fruit length: 4 to 12 inches
Fruit covering: fleshy; hard-shelled berry
Fruit color: turns from green to yellow when ripe
Fruit characteristics: does not attract wildlife; showy; fruit/leaves not a litter problem
Fruiting: year-round
Figure 5. Fruit—Crescentia cujete: Calabash
Trunk and Branches
Trunk/branches: branches droop; showy; typically multi-trunked; no thorns
Bark: gray to brown and smooth, becoming scaly and fissured with age
Calabash should be grown in full sun on any well-drained soil.
The main limbs on calabash originate close to the ground forming a low-branched tree without training or pruning. These limbs branch infrequently, forming a heavy, awkward-looking canopy. This is suitable for planting in an open area where there is plenty of space. Prune the tips of the branches regularly when the tree is young to develop more secondary branches close to the trunk. This will help increase the diameter of the main branches and thicken the canopy. The trunk can be trained straight by staking, and lateral branches directed to grow upright.
Propagation is by seed.
Pests and Diseases
No pests or diseases are of major concern but occasionally bothered by Chinese rose beetles and a leaf-webbing caterpillar.
Reference
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.
