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
Plant type: annual
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
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
Harvest when buds are just cracking, but haven’t fully opened. For double varieties, let open halfway before picking. Expect a vase life of 5 to 6 days.
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
Plant type: annual
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
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
Harvest when buds are just cracking, but haven’t fully opened. For double varieties, let open halfway before picking. Expect a vase life of 5 to 6 days.
Sources
How to Grow
Sources
How to Grow
Seed-Saving Mini Course
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In our upcoming free, three-part video series, you’ll learn everything you need to know to save seeds on a home scale, including how plants are pollinated and isolation techniques to ensure varieties come back true, how to tell when plants are ready to pick and how to harvest the seeds, and how to properly dry, clean, and store seeds long term.
