How to Grow California Poppy
Eschscholzia californica
California Poppies are hardy annuals that thrive in full sun and poor, well-drained soil — the worse the soil, the better they flower. Direct sow only; the taproot makes transplanting almost impossible. Scatter seed in autumn or early spring and barely cover. Thin seedlings to 15 cm apart once established. Virtually no watering, feeding, or pest control needed. Flowers close at night and on cloudy days — this is normal. Deadhead to extend the season or leave seed heads to self-sow freely. A perfect plant for dry, sunny borders and wildflower meadows.
When to Start
Direct sow outdoors as soon as soil reaches 7°C — typically early to mid spring. Hardy enough to tolerate light frosts.
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Growth Stages
Approximate days from start
Care Essentials
- Avoid feeding entirely. Thrives in poor, sandy, well-drained soil — rich soil produces lush foliage but far fewer flowers.
- Virtually pest and disease free. Self-seeds freely and can spread widely — a wonderful low-maintenance wildflower for dry, sunny spots.
Growing Conditions
- Min. soil temperature
- 7°C+
- Germination temperature
- 15–18°C
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- Direct sow
- —
- First harvest
- —
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Spacing & Planting
| Plant spacing | 15 cm |
| Row spacing | 25 cm |
| Sow depth | 0 cm |
| Mature height | 30 cm |
| Mature spread | 25 cm |
Direct sow only — taproot makes transplanting very difficult. Thin to 15 cm apart once seedlings are established.
Pests & Diseases
Pest Aphids
Identification: Small clusters of green or black insects on shoot tips and flower buds, causing distorted growth and sticky honeydew
- Blast off with a strong jet of water
- Spray with fatty acid-based insecticide
- Encourage ladybirds and lacewings
- Spray with a contact insecticide containing deltamethrin or lambda-cyhalothrin
Disease Downy Mildew
Symptoms: Yellow patches on upper leaf surfaces with grey-purple fuzzy growth on the undersides, mainly in very wet conditions
Treatment: Remove affected leaves and improve air circulation. Avoid overhead watering
Prevention: Thin plants to improve airflow, avoid waterlogged soil, and do not overwater
Growing Conditions
| Min. soil temperature | 7°C |
| Germination temperature | 15–18°C |
| Base growth temperature | 5°C |
| Min. daylength to start | 10h |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant California Poppy?
- Plant California Poppy 15cm apart with 25cm between rows.
- When does California Poppy flower?
- California Poppy typically flowers approximately 60 days after transplanting.
- Is California Poppy frost hardy?
- California Poppy is classified as Hardy.
