- Eventual height: 1.2m
- Eventual spread: 0.45m
Cosmos bipinnatus 'Double Dutch White'
cosmos
Delivery options
- Seed Packets (only) £2.95
- Position: Full sun
- Soil: Moderately fertile, moist but well-drained soil
- Rate of growth:Average
- Hardiness: Borderline-hardy (will need winter protection in colder areas
Cosmos makes a great filler for a sunny border, and if dead-headed regularly, ‘Double Dutch White’ is a tall and bushy plant which produces a succession of graceful, double and semi-double, ruffled white flowers from early summer to mid-autumn. It is very easy to grow, and it makes an invaluable addition to the cutting garden.
In early spring, sow seed shallowly in seed trays and keep under glass, transplanting them into individual pots when large enough to handle. Harden off before planting outside after the frosts. Alternatively, sow in-situ in mid- to late spring in a well-prepared bed and thin the seedlings out as they grow to allow approximately 30cm between each.
Seedlings should be potted up and grow on under glass until all risk of frost has passed and they can be planted outside in a well-prepared bed. Pinch out the growing tips to encourage bushier growth, and feed at regular intervals throughout summer with a high-potash fertiliser. Taller plants may need supporting with brushwood stems in exposed positions.
- Sow: August to October or March to April
- Flowering: June to October
- Approximate quantity: seeds