绣球属，又名紫阳花、七变化、洋绣球、粉团花，原产于中国四川一带及日本。原学名八仙花由菲利普·弗兰兹·冯·西博尔德根据其日本妻子的名字-楠本泷所命名。为山茱萸目绣球花科绣球属（学名：Hydrangea）落叶灌木，花几乎全为无性花，所谓的“花”只是萼片而已。早期“花”为白色，后变为蓝色或粉红色。

其性喜阴湿，且对二氧化硫等有害气体抗性强。不可接受过强之直射阳光，否则叶片易灼伤。绣球花的花色可随土壤的pH值而改变。若在酸性土壤种植（pH值比7小），花色是蓝色；若在中性土壤种植（pH值大约等于7），花色是乳白色；若在碱性土壤种植（pH值比7大），花色是红或紫。因此可通过调节土壤的pH值来改变花色。可用扦插法繁殖。

Hydrangea (/haɪˈdreɪndʒⁱə/; common names hydrangea or hortensia) is a genus of 70–75 species of flowering plants native to southern and eastern Asia (China, Japan, Korea, the Himalayas, and Indonesia) and the Americas. By far the greatest species diversity is in eastern Asia, notably China, Japan, and Korea. Most are shrubs 1 to 3 meters tall, but some are small trees, and others lianas reaching up to 30 m (98 ft) by climbing up trees. They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous.