Spiraea japonica ('Shirobana') 'GENPEI'

Spiraea is a common shrub of Central-Europeans parks. This low-maintenance plant is available in many species and varieties each of which offers a different feature. Even thoug public plantings often offer the same one over and over, and the only job done to avoid absolute neglect is radical pruning to bizarre shapes that don’t suit this plant at all, spiraea can be a pretty plant if used sporadically and well located in the garden.

Genpei is a newer preferred name for this variety of Japanese spiraea that is commonly available in the nursery trade as Shirobana. It is truly an interesting piece with bi-coloured flowers. The corymbs come out in either rich pink colour or pure white. Sometimes one corymb may consist of flowers of both the colours and it has nothing to do with flower maturity. The leaves are a little darker green than on the species, more narrowly elliptic, shallowly serrated at margins. If regularly deadhead, at least once a week, the shrub will continue looking pretty and fresh without those ugly and dry seedpods. Moreover, blooming can be extended to early September this way. It naturally forms a low shrub of somewhat prostrate habit if neglected.

Spring pruning will encourage new growths and the plant will get thicker and will flower more profusely. You can cut off up to two thirds of previous year’s growth or trim the twigs to achieve a desired shape. It is widely soil adaptable but does best in slightly acidic, fertile, constantly moist soil in full sun. Fully hardy to about -34°C (USDA zone 4) and suitable for outdoor pots.

Last update 04-02-2014