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Cosmos 'Double Dutch White'

Flowers

Cosmos 'Double Dutch White'

Cosmos

RHS Plants for Pollinators

These large white Cosmos with a yellow centre, produce masses of blooms over many weeks. Great for cutting with strong stems that hold flowers upright. Equally useful in filling gaps in existing borders for the summer season. Easy to grow and fast growing.

Plant type
Half-Hardy Annual
Position
Full Sun
Height
1.2m
Spread
30cm

Growing calendar

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Sow indoors
Sow outdoors
Flowering

Sowing & growing

Sow where they are to flower once risk of frost has passed. Sow March-May under glass in moist seed compost. Lightly cover with thin layer of soil. Propagate at 15-20°C. Transplant seedlings when they are large enough to handle and grow on. Acclimatise before planting out 30cm apart.

Aftercare

For bushier plants, pinch out growing tips when plants reach 15-20cm tall. Deadhead regularly for more blooms. Stems may require staking.

Ref. SEC084