Cosmos Seeds,
Xanthos

Plant Xanthos cosmos only after all danger of frost has passed and when temperatures reach 70-75 F. The soil should be at least 60 F warm. This variety is not frost-hardy, so be sure to check your local area's last frost date before planting. Flowers typically appear 60-90 days after sowing and will continue blooming through summer and into early fall until the first frost. Learn more about your region's frost dates by checking out our blog post, 'Our Experts Answer Questions, Share Resources.'

Sow cosmos seeds directly in the garden after the last frost or start indoors 3-4 weeks earlier to extend the growing season. Plant seeds 1/8-1/4 inch deep, as they require some light to germinate. Space plants about 10 inches apart to ensure good airflow and enough room for growth. Germination usually takes 7-14 days. For the best flowering, choose a location that receives at least 6-8 hours of direct sunlight daily.

Xanthos cosmos performs best in light, well-draining, average to poor soil. Rich soil can lead to more leaves and fewer blooms. Water sparingly, allowing the soil to dry between waterings to prevent leggy growth. This is a compact variety that generally doesn’t need staking. Avoid excessive moisture and humidity or cool temperatures.

• Cosmos are insect pollinated, and there may be some crossing between varieties in the garden. You can enjoy the mixing or use caging techniques and hand pollination to avoid crossing.
• Saving seeds from cosmos is easy: simply allow the heads to brown and dry on plants and collect seeds. Store in a cool, dry, dark place over winter.