cosmos, chocolate

chocolate cosmos | cosmos atrosanguineus | chocoladecosmos

dye material: flowers

burgundy | blue



This type of cosmos, also known as chocolate cosmos, is originally from Mexico and quite popular worldwide as a cultivated plant. Its stunning petals range from dark red to an almost brown maroon. The Latin name cosmos atrosanguineus, comes from atro, meaning dark, and sanguineus, meaning blood red. 

 It has often been claimed to be extinct in the wild and is mostly cultivated from seeds – but here and there chocolate cosmos reappears and still thrives today. The plant’s more common name chocolate cosmos comes from its smell which gives hints of chocolate. The smell becomes more noticeable towards the end of the day but should not be mistaken – the plant is actually toxic to humans. However, it has other purposes such as making it a popular pollinator by attracting bees and butterflies. And last but not least, this velvety red flowering plant can produce beautiful hues of burgundy dye. 



planting period
(after the last frost date)

harvest period

ph 6-7
prefers well-drained, light and fertile soil

full sun-partial shade

every 2-3 days
once established, chocolate cosmos are relatively drought-tolerant

0,3cm deep
30-45cm apart

seed preparation(optional): Soak the seeds in warm water for a few hours before planting. This can help soften the seed coat and promote germination.
Sow the chocolate cosmos seeds onto the soil surface, pressing them lightly into the mix. Do not cover the seeds with soil, as they require light to germinate.Water gently to not displace the seeds.
During the germination process, it’s best to keep the conditions around 21-24°C with 14-16 hours of sunlight exposure per day.
As the chocolate cosmos plants are quite sensitive during the germination process, it might be a good idea to start the germination inside, in small pots using a seed starter mix, to have greater control over the growing environment.
Chocolate cosmos seeds typically germinate in 7-14 days under optimal conditions.Once the seedlings have developed a couple of true leaves and are large enough to handle, transplant them into the garden after the threat of frost has passed.

mulching: mulch around the stem of the plants to conserve moisture and suppress weeds. 
staking: While chocolate cosmos generally have sturdy stems, taller varieties may benefit from staking to prevent flopping.
end-of-season cleanup: In late winter to early fall, cut back the remaining foliage to the ground after it has died back. This helps with preparing the cosmos for its next growing season.

flower harvest
Deadhead the fully developed flowers regularly to increase continuous blooming, leading to more dye matter within one blooming cycle as well as preventing self-seeding. Therefore, place two fingers below the flower crown and apply soft pressure upwards till the flower snaps off close to the stem. Use the flowers right away or place them onto a paper towel to dry before storing.


mordant dyes

aluin mordant



iron mordant