Lilac — Syringa (Lilac) is a genus of about 20–25 species of flowering plants in the olive family (Oleaceae), native to Europe and Asia.
They are deciduous shrubs or small trees, ranging in size from 2–10 m tall, with stems up to 20–30 cm diameter. The leaves are opposite (occasionally in whorls of three), and in most species simple and heart-shaped to broad lanceolate, but pinnate in a few species (e.g. S. protolaciniata, S. pinnatifolia). The flowers are produced in spring, each flower being 5–10 mm in diameter with a four-lobed corolla, the corolla tube narrow, 5–20 mm long; they are bisexual, with fertile stamens and stigma in each flower. The usual flower colour is a shade of purple (often a light purple or lilac), but white and pale pink are also found. The flowers grow in large panicles, and in several species have a strong fragrance. Flowering varies between mid spring to early summer, depending on the species. The fruit is a dry, brown capsule, splitting in two at maturity to release the two winged seeds.
Lilacs are popular shrubs in parks and gardens throughout the temperate zone. In addition to the species listed above, several hybrids and numerous cultivars have been developed. The term French lilac is often used to refer to modern double-flowered cultivars, thanks to the work of prolific breeder Victor Lemoine.