When Is the Blooming Season for Spiraea thunbergii? A Detailed Guide to Its Flowering Time

Spiraea thunbergii is native to China and Japan and is a shrub in the genus Sorbaria of the Rosaceae family. It gets its name because its flowers are dense and pure white when it blooms. So, when is the blooming season of Spiraea thunbergii? How should it be pruned after flowering?

1. When is the blooming season of Spiraea thunbergii?

The blooming season of Spiraea thunbergii is March to April. In the Yangtze River Delta region, it reaches full bloom in late March; in Shanghai, the blooming season is mid-to-late March; in the north, the blooming season is about 1 month later. When it blooms, the flowers and leaves emerge together. The flowers are white, and the blooming season lasts two weeks. The flowers are small and dense, with 3 to 5 flowers forming an umbel, borne on the middle and upper parts of the slender, soft branches, forming a bright white line.

2. How should Spiraea thunbergii be pruned after flowering?

Spiraea thunbergii is also known as pearl flower, linear-leaf spiraea, sorbaria, snow willow, five-grain tree, street-crossing willow, rice willow, and so on. After flowering, promptly prune away remaining flower branches, diseased and pest-infested branches, and old and weak branches to keep the plant shape neat, avoid nutrient consumption, and promote robust growth with abundant flowers and lush leaves.