Cosmos bipinnatus 'Purity'
- Position: full sun
- Soil: moderately fertile, moist, well-drained soil
- Rate of growth: average
- Flowering period: June to October
- Hardiness: half hardy annual
This popular annual cosmos makes a great filler plant for a sunny border, and as long as it's dead-headed regularly, it will produce a succession of graceful, pure white, saucer-shaped flowers from early summer to mid autumn. It is very easy to grow, and it makes an invaluable addition to the cutting garden.
- Garden care:In early spring, sow 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. As the seedlings grow, pinch out the tips to encourage bushier plants. Taller plants may need supporting with brushwood stems in exposed positions.
- Sow: March-May
- Flowering: June-October
- Approximate quantity: 100 seeds.
Fast-maturing annuals, such as calendula, candytuft, clarkia, cosmos, godetia and nasturtium, can still be sown now for a succession of colour throughout the summer months. If you live in a mild area, make three or four sowings spaced two weeks apart fromRead full article
Deadheading will prevent them setting seed and so use their energy producing a further flush of blooms later on. Plants that respond well to deadheading include annuals such as Ageratum, Alyssum, Antirrhinum, Calendula, Centaurea, Cosmos, Dahlia, foxgloveRead full article