Ajuntament de Barcelona

Poncirus trifoliata

Mossèn Cinto Verdaguer Garden

    Spanish name: 
    Naranjo espinoso
    English name: 
    Hardy orange
    Botanical synonyms: 
    Citrus trifoliata
    Species characteristics
    Family: 
    Rutàcies
    Origin: 
    Northern China
    Habitat: 
    Humid soils, from sandy to clayey
    Characteristics: 

    Deciduous shrub, 3-5 m tall, although occasionally it can reach 8 m, with abundant greenish long and angular branches that have strong prickles, up to 5 cm long.

    The leaves are trifoliate, sometimes pentafoliate, and have obovate to elliptic obtuse leaflets 3-6 cm long (the central one is the longest one). They are dark green and slightly leathery and their margin has small rounded jags.

    The flowers, axillarys and 3-5 cm in diameter, have five white membranous petals and appear isolated or into pairs. They are very bright, colourful and fragrant, although less than orange or lemon blossom.

    The fruit is a globose or pear-shaped fragrant hesperidium (berry that is typical of the citrus fruits), 3-5 cm in diameter. Its colour varies from lemon yellow to golden yellow when ripe. The thick and slightly velvety skin sometimes has ribs. It is rough and covered by visible oily glands. The scarce and acid pulp preserves many ovoid greyish seeds.

    Flowering time: 
    Summer
    Fruiting time: 
    Winter
    Uses and properties: 

    Although fruits from the Hardy Orange tree are of little commercial value because of its acidity, they are edible and used in some countries to produce melmelades with a bitter, strong taste. In China they are used for seasoning and sweets and its skin is used in medicine.

    In gardening is used to build fences and as a base for inserts in other fruit trees, mainly mandarine and orange tree, speeding the process of maturation.

    It's one of the most resilient trees in its family to diseases and cold weather. It can tolerate temperatures of down to 20 Celsius degrees below zero.

    History and curiosities: 

    The scientific name, Poncirus trifoliata, consists of the genus name Poncirus, from the French poncire, "citron", and the Latin term trifoliata, "of three leaves", compound by the prefix tri-, "three", and folia, "leaf".

    The tree was brought to Japan and Europe, together with other citrus fruits, in the 8th c. from Northern China, where it is cultivated since thousands of years ago. Initially, Linnaeus classified the plant in the Citrus genus (with the name Citrus trifoliata), but in 1838 Constantine Rafinesque moved it to the Poncirus genus, of which it is the only species.

    For further information: 

    LÓPEZ GONZÁLEZ, Ginés A. Los árboles y arbustos de la Península Ibérica e Islas Baleares. (2 vol.) Madrid: Mundi-Prensa, 2001