Sweet pea, Lathyrus odoratus, a climbing or nonclimbing annual herb in the pea family, Leguminosae

Sweet Pea (Lathyrus odoratus) is a flowering plant in the genus Lathyrus in the family Fabaceae (legumes), native to the eastern Mediterranean region from Sicily east to Crete.

It is an annual climbing plant, growing to a height of 1-2 m where suitable support is available. The leaves are pinnate with two leaflets and a terminal tendril, this twining round supporting plants to help it climb. The flowers are purple, 2-3.5 cm broad, in the wild plant, larger and very variable in colour in the many cultivars. Unlike most peas, the seeds of the sweet pea are poisonous as they contain a neurotoxin, and should not be eaten. The illness caused by the ingestion of sweet peas is known as odoratism, or sweet pea lathyrism.

Sweet peas have been cultivated since the 17th century and a vast number of cultivars are commercially available. They are often grown by gardeners for their bright colours and the sweet fragrance that gives them their name.
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