Cosmos-atrosanguineus.jpg. by Warden. CC BY-SA 3.0. via Wikimedia Commons
CC BY-SA 3.0 · Wikimedia Commons
Chocolate Cosmos Plant Care
Cosmos atrosanguineus (Hook.) Voss
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.[4] Its dark red to brownish red flowers have a scent resembling chocolate, which is one reason for its popularity as a cultivated plant.
Every 3–5 days
Full sun
50–80°F
40–60%
What Is the Chocolate Cosmos?
Chocolate Cosmos (Cosmos atrosanguineus) belongs to the Asteraceae family within the Cosmos genus. Chocolate Cosmos is native to Mexico. Chocolate Cosmos is also known as Black Cosmos, Bidens atrosanguinea, Cosmos diversifolius.
Chocolate Cosmos displays an upright, bushy annual growth habit, reaching up to 2 inches tall with a spread of approximately 1.5 inches. Chocolate Cosmos produces colorful daisy-like flowers in shades of pink, white, and purple.
Leaf size: approximately 3 inches.
How Often Should You Water a Chocolate Cosmos?
Cosmos atrosanguineus requires watering every 3–5 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 3–5 days
Let soil partially dry between waterings
What Light Does the Chocolate Cosmos Need?
Chocolate Cosmos thrives in full sun light conditions. The optimal light range is 2000–4000 lux. Avoid placing Chocolate Cosmos in direct, harsh sunlight for extended periods, as this can scorch the foliage.
Light Requirement
Full sun
2000–4000 lux
What Temperature and Humidity Does the Chocolate Cosmos Prefer?
Cosmos atrosanguineus grows best at temperatures between 50°F and 80°F. Chocolate Cosmos prefers humidity levels of 40–60%.
Temperature
50–80°F
Humidity
40–60%
What Soil Mix Works Best for a Chocolate Cosmos?
Well-draining, fertile soil with a mix of compost and sand. Good drainage is essential for Chocolate Cosmos to prevent waterlogging, which leads to root rot and fungal issues.
How Do You Repot a Chocolate Cosmos?
Not applicable as an annual plant. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Chocolate Cosmos?
Chocolate Cosmos can be propagated through seeds. Similar propagation techniques also apply to cosmos plant care, which shares the same genus.
Fertilizing
Every 4 months
During the growing season
Is the Chocolate Cosmos Toxic to Pets and Children?
Non-Toxic
Non-toxic to humans and pets
What Pests and Diseases Affect the Chocolate Cosmos?
Chocolate Cosmos is susceptible to aphids, spider mites, whiteflies. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
What USDA Hardiness Zone Does the Chocolate Cosmos Need?
Chocolate Cosmos grows outdoors in USDA Zone 12a. Native to Mexico, Chocolate Cosmos is adapted to warm climates. In cooler regions, grow Chocolate Cosmos as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Chocolate Cosmos is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Cosmos genus — compare its care with other Cosmos species on PlantoScan.
Chocolate Cosmos thrives in bright light and direct sun — see other bright-light plants.
More Cosmos Species
Other Cosmos species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
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