Cosmos sulphureus

Tried and Trouble-free Recommended by 3 Professionals
Common Name: cosmos
Type: Annual
Family: Asteraceae
Native Range: North, Central, and South America
Zone: 2 to 11
Height: 2.00 to 6.00 feet
Spread: 1.00 to 3.00 feet
Bloom Time: June to September
Bloom Description: Yellow
Sun: Full sun
Water: Dry to medium
Maintenance: Medium
Suggested Use: Annual
Flower: Showy
Attracts: Butterflies
Tolerate: Drought, Dry Soil

Culture

Cosmos sulphureus is an annual that is easily grown in average, medium moisture, well-drained soils in full sun. Tolerates dryish soils. Also tolerates poor soils. Avoid rich fertile soils because plants may grow too tall and flop over. Plant seed in the garden just before last spring frost date. Seed may also be started indoors about 4-6 weeks prior to the last spring frost date. Deadhead spend flowers to prolong bloom. Taller plants may be cut back. Plants will sometimes self-seed, particularly if seed drops on bare ground. Self-seeding may rise to the level of being aggressive in some climates and conditions. Seed may be harvested in fall for planting the following spring.

Noteworthy Characteristics

Cosmos sulphureus is native to Mexico. It is an upright, hairy-stemmed, warm-weather annual that typically grows to 1-3’ tall, but can grow to as much as 6’ tall. It produces daisy-like flowers (to 2.5” diameter) with yellow discs and yellow rays. Leaves (to 12” long) are 2-3 pinnate with lanceolate leaflets. Popular cultivars of this species are in many cases compact to dwarf plants with semi-double to double flowers and with flower colors ranging from orange to yellow to scarlet red. Genus name comes from the Greek word kosmos which means decoration or ornament. Additional common names for this plant include yellow cosmos and orange cosmos.

Genus name comes from the Greek word kosmos meaning beautiful.

Specific epithet means sulfur-yellow.

Problems

No serious insect or disease problems.

Garden Uses

Beds and borders. Cottage gardens. Cutting gardens. Wild areas.