garden cosmos, Mexican aster, cosmea, Spanish needles
Tall growing, annual plant with delicate, finely divided foliage. Native to Mexico and southern USA, but naturalised in many parts of the world. Summer flowering with white, pink, or crimson, daisy-like, 8 cm wide flowers with a yellow centre. Attracts butterflies. Many cultivars have been introduced, including dwarf ones (Sonata series) that grow 30-50 cm tall.
Cosmos bipinnatus prefers a sunny position in well-draining soil. Self-seeds and easy to propagate from seed. Pinch out the tip once the plant is about 15-20 cm tall, to encourage branching. When it reaches flowering size, the plant usually becomes somewhat top-heavy, so will need staking. Deadhead to prolong the flowering season. May suffer from grey mould, aphids, and slugs.
Cosmos is an annual plant, so it flowers, seeds set, and then dies within one year. Once you have planted this in your garden, new seedlings will appear in subsequent years (as long as you give the plants a chance to form seeds before cutting off the spent flowers). Lovely flowering plant for the middle or back of borders. Flowers last a bit more than a week on water.
Type of plantHerbaceous - Annual
Size.3 to 2 m tall depending on the variety
Landscape Useflower display, cottage gardens, cut flower
- Temperature: Half hardy
- Light: High
- Moisture: Medium
- Soil: Light Medium Heavy
- Wind tolerance: Low