Gardenia jasminoides



Gardenia jasminoides cv.

J.Ellis 1761

pronounced: gar-DEEN-ee-uh jaz-min-OY-deez

(Rubiaceae — the gardenia family)


common name: gardenia

Gardenia was named by Linnaeus after Dr. Alexander Garden (1730–1791), a Scottish physician who emigrated to South Carolina and corresponded with Linnaeus about American plants; jasminoides is botanical Latin for ‘jasmine-like’.

Gardenias are evergreen shrubs and small trees growing 1 – 5 m tall. The leaves are opposite or in whorls of 3 or 4, 5 – 50 cm long and 3 – 25 cm broad, dark green and glossy with a leathery texture.

The flowers are solitary or in small clusters, white, or pale yellow, with a tubular-based corolla with 5 – 12 petals from 5 – 12 cm in diameter. Many species are strongly scented. The flowers are produced on or at the ends of branches. Cultivated forms often have double rose-like flowers, that open from large buds with a distinctive whorl of petals. Fleshy or leathery berries then follow. Gardenias will persist in a wide range of conditions, but if they are not perfectly content, they will tend to look quite awful. They seem to do best in a protected corner of the garden with some morning sun – they don’t like the full glare of the afternoon sun.

There are over 200 species of gardenias, but most of them are hybrid varieties. Apart from Gardenia jasminoides, the other most common types of gardenia are:

      • Gardenia augusta;
      • Gardenia thunbergia, also known as Star Gardenia; this can be a shrub or a small tree, and grows to about 1.2 – 1.5 m tall;
      • Gardenia nitida, a sturdy plant that can reach almost 1.5 m when taken care of properly and well maintained;
      • Gardenia radicans, a dwarf variety that grows to about 45 cm, and produces double blooms.

Gardenias originated in China and Japan, and are now found in Africa, Asia and Australasia. They are attractive landscape subjects in warm climates, and make good container plants. The flowers of some species are used to perfume tea, and others are used to treat influenza and colds in modern Chinese herbalism. A yellow dye was made from the fruits.

Gardenias tend to leach trace elements from the soil. Patterning yellow of the leaves may indicate manganese or magnesium deficiencies, and these can be corrected by the addition of appropriate trace elements, or using an enriched fertilizer; but it is quite usual for the lower leaves of healthy plants to turn yellow and fall off as new growth is made at the head of the branches. The root system is shallow and sensitive, so a thick layer of mulch to control weeds is better than cultivating.

I think the cultivar pictured is ‘August Beauty’, but I am not absolutely certain.

The gardenia is a food plant for several caterpillars, including those of:
      • the moth Parotis marginata;
      • the Twig Looper Ectropis excursaria;
      • the moth Chalcocelis albiguttatus;
      • the Coffee Hawk Moth Cephonodes hylas; and
      • the Gardenia Bee Hawk Cephonodes kingii.


Information about medicinal qualities of plants, or about their use as medicines, is for interest only, and is not intended to be used as a guide for the treatment of medical conditions.


Photograph taken Picnic Bay 2010
Page last updated 3rd January 2019