Cosmos atrosanguineus
Common name(s): chocolate cosmos
Description: perennial; velvety, deep burgundy flowers with a rich chocolate fragrance that is most noticeable in warm, sunny weather. Blooms all throughout the summer and into autumn. Roots are tuberous (much like dahlias) and depend upon freely draining soil to prevent rot during cold, wet weather.
Height: to 30 in. Spread: to 18 in.
Position: full sun and well-draining soil
Uses: ornamental, to attract pollinators
Winter Hardiness: to 10 F and below with sufficient drainage. One strategy for ensuring its survival is to dig up (lift) the tubers in late autumn once the plant is fully dormant and store them inside until the last hard frost has passed.
Care: deadheading will promote additional blooms but is not necessary