Cosmos Sea Shell Red – “Cosmos bipinnatus”

Romantic flutes of scarlet beauty!

Cosmos bipinnatus ‘Sea Shells Red’ is a dazzling, free-flowering variety with uniquely tubular petals that resemble seashells. The blooms shimmer in shades of deep crimson to ruby red, dancing above fine, feathery foliage. A garden favourite and florist’s delight, this cosmos is quick to grow, long-blooming, and irresistible to pollinators. With its whimsical, shell-like petals, it adds both elegance and playfulness to summer bouquets.

🌱 How to Grow:

Sowing Time (South Africa):
Spring to midsummer (September–January).
Direct sow in garden beds once frost danger has passed, or start in trays for earlier blooms.

Germination:
7–10 days at 18–24°C.
Sow 3–5 mm deep, keep soil lightly moist until seedlings emerge.

Transplanting:
Transplant when 5–7 cm tall.
Space 25–40 cm apart for branching growth and abundant flowers.
Cosmos don’t mind transplanting but handle with care.

🌞 Position:
Full sun — 6–8 hours daily for strong, tall stems and abundant blooms.

🪨 Soil:
Light, well-draining soil.
Moderately fertile — too much fertility = lots of leaves, fewer flowers.
pH: Neutral to slightly alkaline (6.0–7.5).

💧 Watering:
Low to moderate water needs.
Water deeply once or twice a week.
Tolerates dry spells but avoid prolonged drought during flowering.

🌼 Flowering Time:
Blooms 10–12 weeks after sowing.
Produces waves of flowers all summer into autumn if regularly cut.

📏 Height & Spread:
90–120 cm tall.
30–50 cm wide.
Produces masses of long, airy stems ideal for cutting.

🌿 Top Tips:
✔️ Cut frequently to promote more blooms.
✔️ Harvest when petals just begin to unfurl for longest vase life.
✔️ No pinching needed, but pinching at 30 cm encourages bushier plants.
✔️ Tolerates poor soils and dry conditions — fuss-free cut flower.
✔️ Stagger sowings every 2–3 weeks for continuous harvest.

🐝 Pollinator Friendly:
Bees, butterflies, and hoverflies flock to its nectar-rich blooms!