ABSTRACT
Clerodendrum comprises mostly tropical shrubs and trees. No commercial cultivars are available, but a clone was selected which flowered profusely on short shoots and one which showed a lesser tendency to flower abscission than usual. Flower abscission is a major problem in the introduction of this plant as a florist crop. Even though C. thomsoniae is a twining plant, compact plants with short flowering shoots may be obtained. C. thomsoniae Balf. f. is a tall twining, glabrous evergreen shrub with opposite, ovate, and prominently veined leaves. The flowers are borne in lax forking axillary racemes. Since flowering primarily occurs in spring, and mostly twining, nonflowering shoots occur in summer, daylength may influence growth and flowering. Substances which favor stem elongation inhibit flowering, while substances which inhibit stem elongation favor flowering. Ancymidol seems to be the tool by which Clerodendrum thomsoniae can be transformed to a compact flowering pot plant.
