Siam Villa Garden: Water Jasmine

English Name: Water Jasmine

Scientific Name: Wrightia religiosa Benth

Family: Apocynaceae

Native Region: China, Indochina, Malaysia, Philippines, Thailand

Water Jasmine has light green lanceolate leaves which are arranged in an opposite pattern. The flowers are white, pendulous, and fragrant. If they are pollinated by insects, long green seed pods develop which look like pairs of beans. The water jasmine takes constant pruning well and ramifies willingly. In tropical countries it is therefore often planted to form hedges. The bark and the roots of the water jasmine are used for medicinal purposes in some countries. The Wrightia religiosa, like its botanical name suggests, is a holy plant for the buddhists. It is planted in many temples and house gardens.

The Water Jasmine is a tropical tree species which is native to China, Indochine and Malaysia and can become up to 20 ft tall. It has a smooth grey bark and prominent surface roots. In Southeast Asian countries the water jasmine is often used for bonsai.

The water jasmine loves heat and likes to be placed in full sun. Temperatures should be above 65° F. If it gets colder, the tree can be semi-deciduous during winter. In autumn, when temperatures drop, the tree must be taken into the house and should be placed at a window where it gets as much light as possible. Grow lights can be necessary.

Larger branches can be pruned in spring before the new strong growth begins. Back budding will work well after heavy pruning. The water jasmine grows very vigorously and, for the development of a good ramification, new shoots are constantly trimmed back to one leaf pair after several leaf pairs have developed. Flowers can appear after the third leaf pair has grown. In tropical climate the water jasmine bonsai can be defoliated several times a year to increase twigging and reduce the leaf size. The younger branches and twigs can be wired but because of the strong growth of this species you must take very good care to remove the wire in time before it bites into the bark. Guy wires or strings are a good alternative.

Water jasmine can be propagated from seeds, branch cuttings and root cuttings. Air-layering is also possible.