Forsythia is a genus of flowering plants in the family Oleaceae (olive family). There are about 11 species, mostly native to eastern Asia, but one native to southeastern Europe. The common name is also Forsythia; the genus is named after William Forsyth.
Forsythia viridissma, meanwhile, had overtaken it in European gardens. The Scottish plant-hunter Robert Fortune "discovered" it— in a mandarin's garden of the coastal city of Chusan (Zhoushan)— before he ever saw it growing wild in the mountains in Chusan's province, Zhejiang.
The hybrids Forsythia × intermedia (F. suspensa × F. viridissima) and Forsythia × variabilis (F. ovata × F. suspensa) have been produced in cultivation. Forsythia intermedia is a hybrid between F. suspensa and F. viridissima. Many cultivars have been selected from this cross including dwarf and compact forms.