50 Pack of Bright Lights Cosmo Seeds
 
Basic Plant Profile
Botanical name: Cosmos sulphureus
Common name: Bright Lights Cosmos
Type: Annual
Height: 2–4 ft (60–120 cm)
Spread: 12–24 in (30–60 cm)
Bloom time: Mid-summer to frost
Pollinators: Bees, butterflies, and beneficial insects
Light Requirements
Full sun (6+ hours per day) is essential for strong stems and abundant blooms.
Can tolerate partial sun but will become leggy and bloom less.
Climate & Temperature
Thrives in warm weather; heat-tolerant.
Performs in USDA zones 2–11 as a summer annual.
Seeds germinate well when soil is 65–75°F (18–24°C).
Soil Requirements
Prefers poor to average, well-drained soil.
Avoid rich soil—too much fertility makes tall, floppy plants with fewer flowers.
pH: 6.0–7.0 (but very tolerant).
Watering
Drought-tolerant once established.
Water regularly for the first weeks, then reduce frequency.
Allow soil to dry between waterings; avoid overwatering.
Sowing & Planting - Direct Sowing (recommended)
Sow outdoors after frost danger has passed.
Cover seeds lightly—about ¼ inch (6 mm).
Germination: 7–14 days.
Spacing: 6 - 12 in apart for airflow and sturdier growth.
Care & Maintenance
Deadhead regularly to promote continuous blooming.
Stake tall plants if your site is windy.
Do not fertilize—this reduces flowering.
Harvesting for Cut Flowers
Cut stems when the flowers are just opening.
Place in water immediately.
Cosmos last 5–7 days in a vase.
Saving Seeds
Let some blooms dry on the stem until seed heads turn brown.
Collect seeds and store dry; they self-seed readily in the garden.