lilac
Syringa L.
A genus overview; characteristics vary between its species.
Lilacs range from densely twiggy shrubs to small trees. Common lilac, Syringa vulgaris, has given rise to hundreds of garden cultivars, while tree lilacs develop one or a few main trunks. Their familiar flower clusters are composed of many small individual blossoms, rather than one large flower. Arnold Arboretum: Lilac Collection
Botanical name
Kew accepts Syringa as a genus in the olive family, Oleaceae. This profile covers lilacs collectively. Kew Plants of the World Online: Syringa
Recognizing the plant
The leaves grow in opposite pairs. Most species have simple, unlobed blades, but the genus includes striking exceptions: Syringa pinnatifolia has compound leaves, and S. protolaciniata has deeply divided blades. Typical flowers have a small persistent calyx, four spreading or upright corolla lobes and two stamens. Depending on the species, the corolla forms a slender tube, a funnel or a more open shape. Dry, slightly flattened capsules eventually split to release narrow-winged seeds. Flora of China: SyringaArnold Arboretum: Lilac Collection
Seasonality across the genus
Boston, Massachusetts, cultivated collection
At the Arnold Arboretum, different lilacs extend the spring display over about five weeks; Japanese tree lilac flowers later than common lilac. Arnold Arboretum: Lilac Collection
Native range
The genus is native to southeastern Europe and parts of Asia, including the Himalayas, China, Korea and Japan. Garden lilacs cultivated elsewhere represent introductions, selected cultivars and hybrids. Kew Plants of the World Online: SyringaFlora of China: SyringaArnold Arboretum: Lilac Collection
Botanical sources
Reviewed 2026-10-11. Seasonal development varies with location and growing conditions.