Cosmos atrosanguineus, commonly known as Chocolate Cosmos, is a herbaceous perennial plant native to Mexico. It grows to 40–60 cm tall and features a fleshy tuberous root. The plant is characterized by its dark red to brownish-red flowers that emit a scent reminiscent of chocolate, contributing to its popularity in gardens. The leaves are 7–15 cm long, pinnate, with leaflets 2–5 cm long. The capitulum measures 3–4.5 cm in diameter, with a ring of six to ten (usually eight) broad ray florets surrounding a center of disc florets. The flowers have a light vanillin fragrance, which intensifies towards the evening. Chocolate Cosmos blooms from mid to late summer and is known for its showy flowers.

Chocolate Cosmos is valued for its unique chocolate scent and striking dark flowers, which make it an excellent choice for sensory gardens and as a conversation piece in borders and containers. It is also used as a cut flower due to its attractive appearance and fragrance. This plant prefers full sun but can tolerate partial shade and requires well-drained soil. It is frost-sensitive and must be protected or lifted in colder climates (Zones 6–11). To overwinter the tuber, it should be dug up and stored in a frost-free location. Chocolate Cosmos may require staking in windy areas and can be susceptible to slugs and snails. It is not known to be invasive but should be monitored to prevent unwanted spread.CC BY-SA 4.0