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Cosmos

Cosmos (KAHS-mos)

Family: Asteraceae Native Herbaceous (3-15 ft)

Cosmos is a genus of about 35 hardy annuals and perennials that are native to North and South America in the daisy family (Asteraceae). The Genus name is from the Greek meaning ordered, referring to the neat arrangement of the flower petals. There are many cultivars available to plant. These plants will grow 1 to 6 feet tall and prefer well-drained average garden soil in full to partial sun. Many varieties can be started from seed in the spring. Do not overwater or over-fertilize, as this will decrease flower production. Deadheading will encourage further blooms. The flowers are in various colors depending on the species and consist of ray petals surrounding a center of disc florets. The foliage can be simple to compound with opposite pairs of leaves. Many will bloom throughout the summer into fall. Several species make good garden plants to add color to the border of a cottage, cutting or butterfly garden. Insects, Diseases, and Other Plant Problems: Issues affecting these plants include aphids, gray mold, stem canker and powdery mildew. Allowing good airflow will help avoid diseases.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 54 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (3-15 ft) Optimal soil pH Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

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.

Full plant profile

Growing Conditions
Plant type
Annual
Life cycle
Annual
USDA zones
2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Occasionally Dry
Available space
12 inches-3 feet; 3 feet-6 feet; 6-feet-12 feet; 12-24 feet; 24-60 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 1 ft. 0 in. - 6 ft. 0 in. | Width: 2 ft. 0 in. - 4 ft. 0 in.
Growth rate
Rapid
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Erect
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately); Simple
Leaf arrangement
Opposite
Leaf shape
Pinnatisect
Leaf margin
Lobed
Leaf feel
Smooth
Hairs present
No
Leaf detail
Finely cut green leaves in thread-like sections. They can be simple or compound depending onthe species.
Flower color
Gold/Yellow; Orange; Pink; Purple/Lavender; Red/Burgundy; White
Flower value
Good Cut; Long Bloom Season; Long-lasting; Showy
Flower form
Head
Flower shape
Saucer
Flower size
3-6 inches
Flower detail
The flowers are saucer shaped, and daisy like. There are many colors available. They sit atop the long, slender stems. Deadhead spent flowers to prolong bloom, but leave enough flower heads for self seeding to take place.
Bloom time
Fall; Spring; Summer
Fruit type
Capsule
Stem detail
Long, slender stems.
Wildlife & Ecology
Native status
Native
Origin
South America, North America, Mexico
Wildlife value
Attracts pollinators and butterflies
Attracts
Bees; Butterflies; Pollinators
Play value
Attractive Flowers; Attracts Pollinators; Colorful; Easy to Grow
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Coastal; Container; Meadow; Naturalized Area; Patio
Landscape theme
Butterfly Garden; Children's Garden; Cottage Garden; Cutting Garden; Pollinator Garden
Design feature
Border; Foundation Planting; Mass Planting
Garden tags
#lilac #showy flowers #drought tolerant #cutting garden #well-drained soil #naturalizes #border planting #naturalized area #full sun tolerant #cottage garden #spring interest #sandy soils tolerant #loamy soils tolerant #butterfly friendly #summer flowers #pink flowers #bedding plants #white flowers #self-seeding #low maintenance #annual #wildflower #hortcontest #poor soil tolerant
Problems & Resistance
Insect problems
Aphids on Ornamental Landscape Plants; Aphids Found on Flowers and Foliage
Disease problems
Southern Blight of Herbaceous Ornamentals
Resistant to
Drought
Propagation
Seed

Planted at Hunnicutt

Nobody’s planted this one yet.