How to Grow Blue Pimpernel
Anagallis monellii
Half Hardy Warm Season
Blue Pimpernel is a sun-loving half-hardy annual grown for its masses of vivid gentian-blue, five-petalled flowers with orange-red centres. Sow indoors in spring and plant out after the last frost in well-drained soil or containers in full sun. Water moderately and avoid waterlogging. Deadhead regularly to keep flowers coming through summer and autumn. Plants are frost-tender and treated as annuals in the UK.
In your Leaftide garden - Hardiness
- Half Hardy
- Season
- Warm Season
- Spacing
- 20 cm
- Height
- 20 cm
- Sow depth
- 0.3 cm
- Min. soil temperature
- 10°C+
- Start from
- Seed
- Light
- Full sun
- Water
- Moderate
When to Start
Sow indoors 6 weeks before last frost, or direct sow outdoors after frost risk has passed and soil reaches 10°C.
Don't know your frost date? Find it here →
Growth Stages
Sow seeds
Day 0 Germination
~14 days Flowering
~110 days Seed to harvest ~110 days
Approximate days from start
Care Essentials
- Feed with a balanced liquid fertilizer every 3–4 weeks during the growing season. Avoid high-nitrogen feeds that encourage leaf growth at the expense of flowers.
- Anagallis monellii thrives in full sun with excellent drainage. The vivid gentian-blue flowers open in sunshine and close at night or on cloudy days. Superb for containers, window boxes, and the front of sunny borders.
Growing Conditions
- Min. soil temperature
- 10°C+
- Germination temperature
- 15–20°C
Don't know your frost date? Find it here
- Sow indoors
- —
- Transplant out
- —
- First harvest
- —
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Spacing & Planting
| Plant spacing | 20 cm |
| Row spacing | 25 cm |
| Sow depth | 0.3 cm |
| Mature height | 20 cm |
| Mature spread | 30 cm |
Growing Conditions
| Min. soil temperature | 10°C |
| Germination temperature | 15–20°C |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant Blue Pimpernel?
- Plant Blue Pimpernel 20cm apart with 25cm between rows.
- When does Blue Pimpernel flower?
- Blue Pimpernel typically flowers approximately 60 days after transplanting.
- Is Blue Pimpernel frost hardy?
- Blue Pimpernel is classified as Half Hardy.