Cosmos Care
Cosmos bipinnatus
An annual with feathery, fine leaves and single pink, white and purple flowers that blooms all summer. It flowers more in poor soil; it can be sown directly from seed.
Monthly care calendar
Timings are for a temperate Northern Hemisphere climate. In warmer areas tasks start earlier, in colder areas later; in the Southern Hemisphere shift them by six months.
- Frost risk: If frost is expected, cover with frost fabric; if in a pot, move to a sheltered place. Damaged below approximately 0 °C.
- Frost risk: If frost is expected, cover with frost fabric; if in a pot, move to a sheltered place. Damaged below approximately 0 °C.
- Frost risk: If frost is expected, cover with frost fabric; if in a pot, move to a sheltered place. Damaged below approximately 0 °C.
- Watering: Water a newly planted specimen more often than established plants during its first year, as its root system is still shallow.
- Plant protection: If symptoms spread and treatment is needed, consult a licensed plant-protection supplier or an agronomist. Plant protection products are regulated; follow local rules.
- General care: Good time for planting and transplanting.
- Pests & diseases: Look for aphids (green or black clusters of small insects) on fresh shoot tips. If there are only a few, you can knock them off with a strong jet of water.
- Watering: Water a newly planted specimen more often than established plants during its first year, as its root system is still shallow.
- Pruning: Regularly remove spent flowers at the base; this encourages new flowering. Remove spent flowers regularly; too much fertilizer makes leaves instead of flowers.
- Plant protection: If symptoms spread and treatment is needed, consult a licensed plant-protection supplier or an agronomist. Plant protection products are regulated; follow local rules.
- General care: Good time for planting and transplanting.
- Pests & diseases: Look for aphids (green or black clusters of small insects) on fresh shoot tips. If there are only a few, you can knock them off with a strong jet of water.
- Watering: In a long drought, water deeply once a month.
- Pruning: Regularly remove spent flowers at the base; this encourages new flowering.
- Plant protection: If symptoms spread and treatment is needed, consult a licensed plant-protection supplier or an agronomist. Plant protection products are regulated; follow local rules.
- General care: Flowering begins.
- Pests & diseases: Look for aphids (green or black clusters of small insects) on fresh shoot tips. If there are only a few, you can knock them off with a strong jet of water.
- Watering: In midsummer, deep watering every 15-20 days is enough. Established plants (over 2 years old) do not need watering in most years. Water so that the soil is wetted to a depth of 10-15 cm from the surface.
- Pruning: Regularly remove spent flowers at the base; this encourages new flowering.
- General care: Flowering continues.
- Watering: In midsummer, deep watering every 15-20 days is enough. Established plants (over 2 years old) do not need watering in most years. Water so that the soil is wetted to a depth of 10-15 cm from the surface.
- Pruning: Regularly remove spent flowers at the base; this encourages new flowering.
- General care: Flowering continues.
- Watering: In a long drought, water deeply once a month.
- Pruning: Regularly remove spent flowers at the base; this encourages new flowering.
- General care: Flowering continues.
- General care: Flowering continues. It is removed at the end of the season; it is replaced with a seasonal change of plants.
- Frost risk: If frost is expected, cover with frost fabric; if in a pot, move to a sheltered place. Damaged below approximately 0 °C.
- Frost risk: If frost is expected, cover with frost fabric; if in a pot, move to a sheltered place. Damaged below approximately 0 °C.
The care advice on this page is general and for information only; it is not professional advice. Plant age, soil and your garden’s microclimate can change the outcome. Plant protection products are mentioned only as general information; they are regulated, and the choice, dose and timing must be decided by a qualified professional under local rules. Consult a landscape architect or agronomist before applying.
Want reminders for every plant in your garden? Our garden-care app with monthly task lists and frost alerts is currently available in Turkish; the English version is on the way.
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