Cosmos

Planting cosmos

Sow directly after the last frost, or start indoors 4 to 5 weeks early for a head start. Cosmos dislike root disturbance, so transplant carefully.

Planting details

• Sow where plants will grow, in full sun
• Spacing: 12 to 18 inches
• Seed depth: about 1/4 inch

Growing requirements

Cosmos prefer lean, well-drained soil and full sun. They tolerate heat and dry spells better than most annuals and need little feeding.

Harvesting and care

Deadhead or cut regularly for bouquets to keep blooms coming. Taller varieties may need staking in windy spots.

Common mistakes

• Rich soil or fertilizer, which produces tall, floppy plants with few flowers
• Overwatering established plants, which reduces flowering
• Crowding seedlings, which limits airflow and encourages weak stems

Companion plants

Cosmos fit well at the back of borders and along fences, and they draw pollinators into vegetable gardens without heavy root competition.