Cosmos atrosanguineus (Hook.) Voss, not Stapf

Cosmos atrosanguineus, the chocolate cosmos, is a species of Cosmos, native to Mexico. It has often been claimed that it is extinct in the wild; however it is "quite abundant" in Mexico. The species was introduced into cultivation in 1885, when the British seed company Thompson & Morgan first listed it in their seed catalogue. Its dark red to brownish red flowers have a scent resembling chocolate, which is one reason for its popularity as a cultivated plant.

Description

Cosmos atrosanguineus is a herbaceous perennial plant growing to 40–60 cm tall, with a fleshy tuberous root. The leaves are 7–15 cm long, pinnate, with leaflets 2–5 cm long. The flowers are produced in a capitulum 3–4.5 cm diameter, dark red to maroon-dark brown, with a ring of six to ten (usually eight) broad ray florets and a center of disc florets; they have a light vanillin fragrance (like many chocolates), which becomes more noticeable towards the end of the day.

 

Cosmos atrosanguineus - Wikipedia