Cosmos
Also called Mexican aster, Garden cosmos.
| Light | full sun |
|---|---|
| Water | Every 6 days in the growing season, every 14 in winter |
| Humidity | medium |
| Difficulty | easy |
| Height | Up to 120 cm (47 in) tall |
| Pets | Cats not known, dogs not known |
Source: ASPCA Animal Poison Control, toxic and non-toxic plants, no entry for Cosmos bipinnatus.
Cosmos is the most generous annual there is, and the trick to it is neglect. It comes from thin Mexican soil, and on rich ground it grows into a great leafy thing that never gets round to flowering. Sow it under cover from February and outdoors once the frosts are past, through to May in the north. In South Africa it is sown in the spring months and is one of the fast maturing annuals recommended for November, which is why the roadsides are full of it by autumn. Sow thinly, thin ruthlessly, and pinch the tips out once so each plant branches. Then pick the flowers, or at least deadhead them, because the plant stops as soon as it sets seed and keeps going for months if you do not let it.
Ailments observed
| It will not flower | Rich soil or a general feed, which cosmos answers with foliage. Stop feeding and let the ground dry a little between waterings. Pinch the growing tips out once when the plant is thirty centimetres tall to make it branch. |
|---|---|
| Limp, drooping leaves | A tall plant knocked sideways by wind and rain. Stake the taller varieties early, before they need it. Once a cosmos has gone over at the base it never stands properly again. |
Filed underPlants that forgive a beginner
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