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Cosmos

Common Name(s):

Phonetic Spelling
KAHS-mos
Description

Cosmos is an easy-to-grow flower that can reseed itself and grow in hot, dry conditions, making it a good choice for North Carolina gardens. The hardy annuals will give you blooms from summer to frost. 

Plant cosmos in a location that receives at least a half-day of direct sunlight. 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.

Be cautious not to overwater your plants.  That and over-fertilizing can lead to the plant producing fewer flowers.

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.

Insects, Diseases, and Other Plant Problems:  Issues effecting this plant include aphids, gray mold, stem canker and powdery mildew.  Allowing good airflow will help avoid diseases.  

See this plant in the following landscape:
Extension Master Gardenerâ„  Demonstration Garden, Durham Co.
Cultivars / Varieties:
Cosmos bipinnatus, Cosmos sulphureus, 'Picotee', 'Purity', 'Sea Shells'
Tags:
#cultivars#showy flowers#full sun tolerant#drought tolerant#lilac#white flowers#pink flowers#low maintenance#cottage garden#well-drained soil#summer flowers#naturalizes#border planting#bedding plants#self-seeding#cutting garden#spring interest#naturalized area#poor soils tolerant#sandy soils tolerant#loamy soils tolerant#butterfly friendly#annual#wildflower
 
Cultivars / Varieties:
Cosmos bipinnatus, Cosmos sulphureus, 'Picotee', 'Purity', 'Sea Shells'
Tags:
#cultivars#showy flowers#full sun tolerant#drought tolerant#lilac#white flowers#pink flowers#low maintenance#cottage garden#well-drained soil#summer flowers#naturalizes#border planting#bedding plants#self-seeding#cutting garden#spring interest#naturalized area#poor soils tolerant#sandy soils tolerant#loamy soils tolerant#butterfly friendly#annual#wildflower
  • Attributes:
    Genus:
    Cosmos
    Family:
    Asteraceae
    Uses (Ethnobotany):
    Cutting garden
    Life Cycle:
    Annual
    Recommended Propagation Strategy:
    Seed
    Country Or Region Of Origin:
    Lesser Sunda Island, Southern America, Northern America, Mexico
    Wildlife Value:
    Attracts pollinators and butterflies
    Play Value:
    Attractive Flowers
    Attracts Pollinators
    Colorful
    Easy to Grow
    Dimensions:
    Height: 1 ft. 0 in. - 6 ft. 0 in.
    Width: 2 ft. 0 in. - 4 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Annual
    Woody Plant Leaf Characteristics:
    Deciduous
    Habit/Form:
    Clumping
    Erect
    Growth Rate:
    Rapid
    Maintenance:
    Low
    Texture:
    Medium
  • Cultural Conditions:
    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 To Plant:
    12 inches-3 feet
    3 feet-6 feet
    6-feet-12 feet
    12-24 feet
    24-60 feet
    NC Region:
    Coastal
    Mountains
    Piedmont
    USDA Plant Hardiness Zone:
    2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
  • Flowers:
    Flower Color:
    Gold/Yellow
    Orange
    Pink
    Purple/Lavender
    Red/Burgundy
    White
    Flower Inflorescence:
    Head
    Flower Value To Gardener:
    Good Cut
    Long Bloom Season
    Long-lasting
    Showy
    Flower Bloom Time:
    Fall
    Spring
    Summer
    Flower Shape:
    Saucer
    Flower Petals:
    7 - 20 petals/rays
    Flower Size:
    3-6 inches
    Flower Description:
    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.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Deciduous
    Leaf Color:
    Green
    Leaf Arrangement:
    Opposite
    Leaf Shape:
    Pinnatisect
    Leaf Margin:
    Lobed
    Hairs Present:
    No
    Leaf Description:
    Finely cut green leaves in thread-like sections
  • Stem:
    Stem Is Aromatic:
    No
    Stem Description:
    Long, slender stems.
  • Landscape:
    Landscape Location:
    Coastal
    Container
    Meadow
    Naturalized Area
    Patio
    Landscape Theme:
    Butterfly Garden
    Children's Garden
    Cottage Garden
    Cutting Garden
    Fairy Garden
    Pollinator Garden
    Design Feature:
    Border
    Foundation Planting
    Mass Planting
    Attracts:
    Bees
    Butterflies
    Pollinators
    Resistance To Challenges:
    Drought