Klondike cosmos is a fast growing annual with golden-yellow or orange flowers in the Asteraceae (daisy) family. It can grow up to 6 feet tall providing sticking color from summer until the first frost. The ‘Cosmic’ series will give you lots of 2-inch double and semi-double bright, non-fading blooms in shades of orange, red, and yellow, and will get 12 to 18 inches tall on well-branched plants. Plant cosmos in a location that receives at least a half-day of direct sunlight in moist to dry, porous soils. Sow the seeds outdoors after the danger of frost is past and when the soil has warmed to at least 65 degrees. Rake seeds into a loose soil; planting seeds too deeply will hinder germination. Keep the soil moist for 5 to 10 days after seeding. Seeds will germinate in 7 to 21 days. Cosmos needs only basic care to provide an abundance of colorful blooms all summer. Taller varieties may need staking if subjected to high winds and frequent storms. When the spring-planted cosmos appears to have an abundance of dried seed, do not remove the plants. Encourage re-bloom by cutting the plants back to 12 to 18 inches high. They will be back in bloom in a month and the seed that is cut off will fall to the ground, germinate in the hot soil, and increase the density of your plant population and the eventual bloom display. Use in the background as a bedding plant or in a cut flower garden. Quick ID Hints : dimorphic involucral bracts in two rows opposite, pinnatifid leaves small heads 1-2" with orange ray flowers Insects, Diseases, and Other Plant Problems: Aphids and Japanese beetles are occasional bests. Bacterial wilt and canker are occasional diseases. It reseeds easily and can become weedy. More information on Cosmos .
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Height: 2 ft. 0 in. - 3 ft. 0 in. | Width: 1 ft. 0 in. - 3 ft. 0 in.
Growth rate
Rapid
Maintenance
Medium
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Pinnatifid
Leaf size
> 6 inches long
Hairs present
No
Leaf detail
Compound leaves are up to 12 inches long with 2-3 deeply cleft leaflets.
Flower color
Gold/Yellow; Orange; Red/Burgundy
Flower value
Good Cut; Long Bloom Season; Long-lasting; Showy
Flower shape
Saucer
Flower size
1-3 inches
Flower detail
Produces daisy-like flowers (to 2.5” diameter) with yellow discs and yellow rays. Terminal, head to 2" diam., on long peduncles 4-8" long. Involucral bracts in two rows; outer row spreading, narrow, inner row appressed to ray flowers, broad, membranous, pigmented. Ray flowers rich orange or pale reddish-yellow, obovate, notched at apex. Disc flowers yellow.
Bloom time
Fall; Spring; Summer
Wildlife & Ecology
Native status
Unknown
Origin
Mexico to Central America
Wildlife value
Attracts pollinators and butterflies
Attracts
Butterflies; Pollinators
Play value
Attractive Flowers; Attracts Pollinators; Colorful; Easy to Grow