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Hardy Orange

Citrus trifoliata (SIH-trus try-foh-lee-AY-tuh)

Family: Rutaceae Non-native Understory (15-40 ft)

Trifoliate orange is a deciduous thorny shrub or small tree in the citrus family (Rutaceae) native to China. The species epithet is Latin for “having three leaflets” and refers to the compound (trifoliolate or ternate) leaves of this species. It was brought into cultivation as a hardy rootstock for grafted citrus trees but has since become popular in its own right. It prefers well-drained, acidic soil in a sunny location and grows up to nearly 20 feet tall. It is intolerant of shady sites and suffers in especially cold winters. The thorns of the trifoliate orange are sharp and numerous. The plant is not for high-traffic areas, but it can make a very effective security hedge. This plant blooms in mid-spring with large, fragrant flowers typical of the genus (although the flowers are not as fragrant as orange blossoms). The lemon-like fruit is exceedingly sour and full of seeds. If eaten in large quantities, the high acidity can cause severe stomach pain and nausea. Some people experience minor skin irritation after handling the fruits or other plant parts in sunlight. Like many plants in the citrus family, it has chemicals in the leaves and fruits that can cause photodermatitis. While the peel and the pulp can be used to make marmalade, the lightly fuzzy, orange fruits are often left on the tree to provide beauty well into winter. Trifoliate orange makes an impenetrable security hedge or an interesting feature specimen in an Asian garden, sensory garden, pollinator garden or edible garden. The fruits add color to a winter garden. It can also grow well in a large container. Quick ID Hints: Lemon-like, lightly fuzzy, fall-ripening, sour fruit Trifoliolate leaves with winged petioles Bright green twigs and numerous, long green thorns Insects, Diseases, and Other Plant Problems: No serious pest or disease problems. It can be weedy and is considered invasive in some states , including in NC by the NC Invasive Plant Council. See native alternatives to the left. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common citrus insect and related pests.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 69 attributes.

How it fits the guild

Guild layer 2 - Understory (15-40 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Jasminum nudiflorum Smilax maritima
Similar, less problematic Crataegus nitida

Full plant profile

Growing Conditions
Plant type
Edible; Perennial; Poisonous; Shrub; Tree
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage
Available space
6-feet-12 feet; 12-24 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 8 ft. 0 in. - 20 ft. 0 in. | Width: 6 ft. 0 in. - 15 ft. 0 in.
Growth rate
Rapid
Maintenance
High
Canopy layer
2 - Understory (15-40 ft)
Form & Appearance
Habit / form
Dense; Oval
Texture
Medium
Foliage
Deciduous
Leaf color
Gold/Yellow; Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Alternate
Leaf shape
Elliptical; Obovate
Leaf margin
Crenate; Serrate
Leaf feel
Glossy
Hairs present
No
Leaf detail
Leaves are alternate and trifoliolate. Leaflets are obovate to elliptic, emarginate, acuminate, crenate to serrate, and the terminal is larger than the laterals. Petiole is winged. Three leaflets emerge yellow-green and turn dark green in the summer. They are yellow in the fall.
Fall color
Gold/Yellow
Flower color
White
Flower value
Fragrant; Showy
Flower size
1-3 inches
Flower detail
Flowers are white, 5-petaled, axillary, solitary in leaf axils, and aromatic.
Bloom time
Spring
Fruit color
Gold/Yellow
Fruit type
Berry
Fruit value
Edible; Fragrant; Showy
Fruit size
1-3 inches long, 1-3 inches wide
Fruit detail
Fruits are modified berries (hesperidium), dull lemon-yellow like a small orange, fragrant when ripe, sour, many-seeded with thick peel and oil glands. The peel is also rough and slightly fuzzy. Though sour, the juice can be used to flavor beverages. It can be used to make marmalade.
Bark color
Green
Bark detail
Green-striped.
Stem color
Green
Stem detail
Spiny, thorny.
Wildlife & Ecology
Native status
Non-native
Origin
Central and northern China
Attracts
Bees
Food & Medicine
Edible parts
Fruit
Harvest time
Fall
Fruit type
Berry

Edibility

This plant is edible

Landscape Use
Landscape theme
Asian Garden; Edible Garden; Garden for the Blind; Pollinator Garden; Winter Garden
Design feature
Accent; Barrier; Hedge; Specimen
Garden tags
#drought tolerant #shrub #deciduous shrub #showy flowers #showy fruits #edible fruits #thorns #fantz #orange fruits #problem for children #high maintenance #aggressive #fragrant leaves #fragrant flowers #weedy #HS303
Problems & Resistance
Problems
Contact Dermatitis; Problem for Children; Spines/Thorns; Weedy
Resistant to
Deer
Propagation
Seed
Poison severity
Low
Poison parts
Fruits
Poison symptoms
Causes only low toxicity if eaten in quantity. Skin irritation minor or lasting only for a few minutes. Furanocoumarins are responsible for photodermatitis, which occurs when the compound is applied to the skin in the presence of sunlight (UV).
Toxic principle
Oil and saponic glycoside. Furanocoumarins.
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Fruits; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.