Cosmos – Sulphur Yellow

The Sulphur Yellow Cosmos thrives in hot, arid climates and is native to Central America. This hardy species can tolerate temperatures of 100°F (38°C) and above, making it well-suited for warm and dry environments.

Cosmos sulphureus produces smaller, bright yellow flowers compared to the larger blooms of Cosmos bipinnatus. This variety typically blooms later in the growing season, adding vibrant color when many other plants begin to fade.

In dry, warm regions, it can be planted in the fall for extended blooming periods. However, in colder or more humid climates, it is best to sow seeds in the spring once the soil has warmed sufficiently. Heat is essential for germination; otherwise, the seeds may remain dormant or rot in cold, wet soil.

This species prefers well-drained, moderately infertile soil. Excessive fertilization can lead to overly lush, weak growth that causes plants to flop. Once established, Sulphur Yellow Cosmos is low maintenance and can thrive with minimal watering and care.

In addition to their ornamental appeal, these cosmos flowers attract birds, bees, and butterflies, promoting garden biodiversity. They also make excellent cut flowers for fresh floral arrangements.

While seeds can be started indoors, they generally perform best when directly sown outdoors in their permanent growing location.

**For larger quantities than listed for sale please contact us for availability and pricing.

The broadcast rate for seeding is 70 – 87.5 pounds per acre.

The seed drill rate for seeding in rows is 35 pounds per acre.