Cosmos ‘Rubenza’
Cosmos bipinnatus
Description
A dramatic addition to any cutting garden, these uncommon cosmos display a vibrant range of colors. The large, single blooms open with deep ruby petals and then fade into shades of muddy rose and terracotta as they age. Cosmos are easy to grow, produce a profusion of blooms, and are perfect for beginners.
Details
Height: 36 to 42 in
Site: full sun
Days to maturity: 75 to 90 days
Plant spacing: 12 in
Pinch: when 8 to 12 in tall
Seed Sowing & Growing Notes
Start seed indoors in trays 4 to 6 weeks before last frost; transplant out after all danger of frost has passed. Cosmos can also be direct-seeded once the weather has warmed.
Harvesting/Vase Life
Details
Description
A dramatic addition to any cutting garden, these uncommon cosmos display a vibrant range of colors. The large, single blooms open with deep ruby petals and then fade into shades of muddy rose and terracotta as they age. Cosmos are easy to grow, produce a profusion of blooms, and are perfect for beginners.
Details
Height: 36 to 42 in
Site: full sun
Days to maturity: 75 to 90 days
Plant spacing: 12 in
Pinch: when 8 to 12 in tall
Seed Sowing & Growing Notes
Start seed indoors in trays 4 to 6 weeks before last frost; transplant out after all danger of frost has passed. Cosmos can also be direct-seeded once the weather has warmed.
Harvesting/Vase Life
Sources
How to Grow
How to Grow

Summer Mini Course
Learn how to grow, harvest & arrange beautiful cut flowers
In our upcoming three-part video series, you’ll learn a simple step to double the number of blooms your plants produce, how to cut and care for your flowers for the longest vase life, and how to make mixed bouquets quickly and efficiently.