Some 150-250, see text Cestrum is a genus of — depending on authority — 150-250 species of flowering plants in the family Solanaceae.

They are native to warm temperate to tropical regions of the Americas, from the southernmost United States (Florida, Texas: day-blooming cestrum, C. diurnum) south to the Bío-Bío Region in central Chile (green cestrum, C. parqui).

Several species are grown as ornamental plants for their strongly scented flowers.

Especially notorious is green cestrum (C. parqui) in Australia, where it can cause serious losses to livestock which eat the leaves (particularly of drying broken branches) unaware of their toxicity.

Like the other hallucinogenic plants consumed by them, Craós wajacas consider it a potent entheogen, not to be taken by the uninitiated.