- USDA hardiness zones:
Native to Mexico, this cosmos 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 2.5î diameter) with yellow discs and yellow rays. Leaves (to 12î 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.
- Full sun
- Dry to medium
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.
Size and growth:
- 2.0 to 6.0 feet
- 1.0 to 3.0 feet
Bloom / flowers:
- June - September
Showy flowers, Annual, Yellow, and Butterflies
North, Central, and South America
Beds and borders. Cottage gardens. Cutting gardens. Wild areas.
No serious insect or disease problems.