Cosmos – Cosmos bipinnatus, C. sulphureus

Common Name: Cosmos

Botanical Name: Cosmos bipinnatus, C. sulphureus, COZ-mos by-pin-NAY-tus and sul-FER-e-us

Decorative Life: 4-6 days.

Flower Color: Orange, Pink, Red, White, Yellow

Availability: Fall, Summer

• Member of the Compositae (aster or sunflower) family.
• Native to Mexico.
• Related species include chrysanthemum, dahlia, marigold, lettuce and zinnia.

• Flower heads up to 4 inches across, consisting of single row of ray flowers surrounded by a yellow center.
• Stems leafy, 16-20 inches long.
• Plant is an annual, classed as a dicotyledon, leaves not parallel veined.
• Flowers are not fragrant.

35F for up to two weeks in water.

• From the Greek “kosmos” (beautiful). The specific epithet names “bipinnatus” and “sulphureus” are in reference to the fine leaf structure and yellow flowers of the respective species.
• Cosmos atrosanguineus is the chocolate cosmos with maroon-crimson flowers, 24 inch stems, and a slight chocolate scent.
• Flowers can be dried with silica gel in 2-3 days.
• The Compositae or aster family is vast, with over 20,000 species, and is also one of the most developed families. It was named Compositae because the flowers are actually a “composite” of many individual flowers into one head. Hence, when children pull one “petal” off at a time, saying “she/he loves me, loves me not”, they are actually removing a complete flower, not just a petal.

Gast (1998) showed that ‘Pied Piper Red’ lasted longer than ‘Purity’, ‘Psyche’ or ‘Daydream’ cultivars and they all exhibited reduced vaselife when held in a flower food solution compared to water alone. Using ‘Sensation’, Redman et al. (2002) reported that 35F storage temperature was best (they did not try lower temperatures). At this temperature flowers could be stored wet for a maximum of two weeks and neither STS or flower food were beneficial in enhancing flower life. Starman et al. (1995) rated ‘Early Wonder’, ‘Versailles Carmine’ and ‘Versailles Red’ as being very good income producers.