Lobularia maritima (syn. Alyssum maritimum; common name Sweet Alyssum or Sweet Alison, also commonly referred to as just Alyssum from the genus in which it was formerly classified) is a low-growing flowering plant in the family Brassicaceae, native to the Mediterranean region and Macaronesia (Canary Islands, Azores).
It is an annual plant (rarely a short-lived perennial plant) growing to 10-30 cm tall. The leaves are 1-4 cm long and 3-5 mm broad, oval to lanceolate, with an entire margin. The flowers are sweet-smelling white (rarely pink or lavender), with four petals; they are produced throughout the growing season, or year-round in areas free of frost.
It prefers partial shade, and is resistant to heat and drought. Plants with darker-colored flowers do better in cooler temperatures.
It has become widely naturalised throughout the temperate regions of the world.
Other synonyms include Alyssum odoratum, Clypeola maritima and Koniga maritima.