Is Cosmos ‘Rubenza’ easy to grow from seed?

Yes. Cosmos Rubenza is very easy to grow from seed and ideal for beginners. Sow directly outdoors or into pots, keep the soil lightly moist, and it will flower reliably throughout summer with minimal care.

When should I sow Cosmos Rubenza seeds in the UK?

Sow Cosmos Rubenza seeds from March to September. Earlier sowings can be started indoors, while later sowings work well direct outdoors once the soil has warmed.

Does Cosmos Rubenza attract bees and butterflies?

Yes. Cosmos bipinnatus ‘Rubenza’ is highly attractive to bees, butterflies, and other pollinators, making it an excellent choice for wildlife-friendly and pollinator gardens.

Is Cosmos Rubenza good for cut flowers?

Absolutely. Cosmos Rubenza produces long, straight stems with rich red blooms that are perfect for cutting. Harvest flowers just as the buds begin to open for the longest vase life.

Cosmos Rubenza seed packet showing deep red cosmos illustration on natural paper background

Cosmos Rubenza flowers with rich velvety red petals fading to warm rose pink in summer border

Close-up of Cosmos Rubenza blooms on long stems with ferny foliage, pollinators visiting

Cosmos 'Rubenza' Seeds

Name: Cosmos 'Rubenza' Seeds
Brand: Herboo
SKU: HS075
Price: 4.00 GBP
Availability: InStock

Cosmos bipinnatus ‘rubenza’

Cosmos bipinnatus ‘Rubenza’ is a standout half-hardy annual with rich, velvety crimson flowers that soften to warm rose tones as they mature, creating a beautiful two-tone effect. With finely divided, ferny foliage and upright stems reaching around 70–75 cm, it’s ideal for cut-flower beds, borders and containers. Thriving in full sun and well-drained soil, this Cosmos variety flowers reliably through summer and early autumn and is loved by pollinators.

Approx 40 seeds

Cut Flowers
Pollinator-Friendly
Compact for Pots
Low Maintenance

Cosmos ‘Rubenza’ is a compact, pollinator-friendly cut flower with dark crimson blooms that fade to soft pink. Easy to grow from seed, it thrives in full sun, flowers all summer, and usually doesn’t need staking in sheltered gardens — perfect for borders, pots and cutting gardens.

Sow:March–September, direct outdoors or in pots
Germination:7-14 days
Grow:Full sun, well-drained soil, space plants 15–20 cm apart
Water:Keep soil lightly moist; avoid waterlogging
Harvest:Cut stems as buds begin to open for longest vase life
Best for:Pots, borders, cut-flower beds

Grow in Your Garden

Rich velvety red blooms, excellent for cutting, pollinator-friendly, and easy to grow in pots or borders.

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4.7

Based on 3 reviews

100% would recommend this product

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3 reviews

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Cosmos 'Rubenza' Seeds