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Cosmos atrosanguineus (Chocolate cosmos, Black cosmos)

Cosmos atrosanguineus Photo/Illustration: Michelle Gervais

(Based on 1 user review)

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Hardiness Zones: 1 2 3 4 5 6 7 8 9 10 11
Botanical Name: Cosmos atrosanguineus KOZ-mose at-tro-san-GWIN-ee-us Common Name: Chocolate cosmos, Black cosmos Synonyms: Bidens atrosanguinea Genus: Cosmos
A chocolate scented flower! Dark red-brown, sometimes almost black, velvety flowers on long, slender, reddish brown stems bloom from early summer to autumn. Chocolate cosmos is a tuberous-rooted, tender perennial native to Mexico that can be overwintered indoors where not hardy. Grow in a border or in containers where the flowers can be appreciated up close. They also make good cut flowers.
 Noteworthy characteristics: Chocolate fragrance; dark, almost black flowers over a long period; good cut flower.
 Care: Grow in moist but well-drained, fertile soil in full sun. Deadhead and provide support. Mulch in autumn where hardy, or lift the tubers and keep frost-free during winter, storing them in barely moist peat.
 Propagation: Root basal cuttings with bottom heat in early spring.
 Problems: Stem canker, powdery mildew, Rhizoctonia stem rot, gray mold, and aphids sometimes cause problems.
Height 1 ft. to 3 ft.
Spread 1 ft. to 3 ft.
Growth Pace Moderate Grower
Light Full Sun Only
Moisture Dry to Medium
Maintenance Moderate
Characteristics Attracts Butterflies; Fragrant Flowers; Showy Flowers
Bloom Time Fall; Summer
Flower Color Brown Flower; Red Flower
Uses Beds and Borders, Container, Cut Flower, Cottage Garden
Seasonal Interest Summer Interest, Fall Interest
Type Perennials

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