BBS Tree of the Month – April 2013

Common Name: Serissa, Tree of a Thousand Stars, Japanese Boxthorn

Species: Serissa foetida – is a flowering semi-evergreen or evergreen shrub native to the sub-tropical woodlands and wetlands of South East Asia, from India, China and Japan growing to a height of 45 – 60 cm. There are different cultivars. The main difference is in the size and shape of the flowers. Snow Rose can only differentiated by measuring the difference in the shape and size of the flowers. Pink Rose has pale pink flowers and leaves edged off-white. Other varieties include Variegated Pink, Pink Mystic, Pink Fairy, Snowflake, Snowleaves, Mt. Fuji, Kyoto and Sapporo. Serissa is used a lot as bonsai, but is a very fussy tree. It drops it leaves if over-watered, under-watered, too cold, too hot, or even moving the tree to a new location. Very often it does not recover from the shock.

Flower/ Leaves/Trunk: Serissa flowers year round, but particularly from early spring to near fall. The 4- to 6-lobed flowers are funnel shaped and 1 cm wide. The buds appear pink but turn to a profusion of white flowers. The leaves are naturally small, oval, deep green, and rather thick. When bruised the leaves have an unpleasant smell, hence its name foetida. The trunk has an attractive rough, grey bark, which tends to get lighter in color with age.

Fertilizer: Every other week during the growing season, at other times once per month. Organic fish emulsion is recommended. As always only fertilize when soil is moist.

Repotting: Serissa dislikes root pruning and can be left for 2-3 years. Repot when average nighttime temperatures are in the low to mid 60 oF. This helps the root system to recover quickly.

Prune/Training: The branches are quite flexible and can be wired. As to pruning Serissa is a hardy plant and can be pruned to shape as needed and responds well to directional pruning. Hard pruning can cause root suckers to develop, which should be removed unless in a multiple tree style and the sucker is needed.

Soil: A well-draining bonsai mix.

Propagation: Softwood cuttings in spring or early summer.

Insect/ Disease: Scale insects. Yellowing leaves and leaf drop caused by incorrect placement, irregular watering and humidity levels.

Watering: Regular watering in a well-draining soil.

Light: Grown in full sun to partial shade.

Temperature: Protect below 50oF. Cold sensitive.

Source: http://www.bonsai4me.com/SpeciesGuide/Serissa.html http://www.bonsaitreegardener.net/serissa-bonsai-tree, http://en.wikipedia.org/wiki/Serissa