How to Grow Scarlett Pimpernel
iNaturalist
Scarlett Pimpernel
Anagallis arvensis
flowerScarlett Pimpernel is a delicate annual wildflower known for its brilliant scarlet-red flowers that close in cloudy weather and at night. Native to the Mediterranean region, it has become naturalized in many temperate regions and is valued for its ornamental beauty and historical significance. The plant is also called Poor Man's Weatherglass due to its flowers' sensitivity to atmospheric conditions.
When should you plant Scarlett Pimpernel in your zone?
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Example Scarlett Pimpernel timeline · Pittsburgh, PA (Zone 6b)
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Plant Scarlett Pimpernel
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Scarlett Pimpernel blooms
Around Jun 1≈ 45 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Scarlett Pimpernel dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-10 as an annual; can self-seed and persist in warmer zones
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Germination
10-14 daysTiny seedlings emerge with threadlike cotyledons; soil should remain consistently moist but not waterlogged
Keep soil surface moist during germination; provide bright light but avoid intense afternoon heat. Germination occurs in 10-14 days at 65-75°F
Seedling
2-3 weeksSmall rosette of narrow, pointed leaves develops; plant remains low to the ground
Thin seedlings to proper spacing once they have true leaves. Reduce watering frequency as plant establishes. Provide good air circulation to prevent damping off
Vegetative Growth
2-3 weeksPlant branches and expands, developing more stems and linear leaves; foliage appears finely textured and delicate
Water moderately; allow light feeding with balanced fertilizer if desired. Pinch back tips to encourage bushier growth. Full sun promotes denser foliage
Flowering
6-8 weeks or until frostDelicate five-petaled scarlet flowers appear at branch tips, typically opening in morning and closing by afternoon or in cloudy weather
Deadhead spent flowers to extend blooming season. Plant is sensitive to humidity and temperature; flowers close in cold or overcast conditions. Provide consistent moisture during flowering
Seed Set and Decline
Until first frostAs temperatures cool or day length shortens, flowering slows and plants produce small round seed capsules; foliage may yellow
Allow some flowers to mature to seed for self-sowing next year, or deadhead to maintain appearance. Plant is frost-tender; remove after final frost or let self-seed
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with water to dislodge; use neem oil or insecticidal soap if severe. Increase humidity and air circulation to deter
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Spray with strong water stream; apply insecticidal soap or neem oil. Encourage beneficial insects like ladybugs
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Use yellow sticky traps; spray with neem oil or insecticidal soap. Improve air circulation
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Remove affected leaves; improve air circulation and avoid overhead watering. Apply fungicide if necessary
Uses
Garden Decoration
OrnamentalScarlett Pimpernel's brilliant red flowers make it an excellent choice for borders, rock gardens, cottage gardens, and wildflower meadows. The delicate blooms attract pollinators and add vibrant color throughout summer. [source]
Weather Prediction
HouseholdTraditionally called Poor Man's Weatherglass, the plant's flowers close in response to humidity changes and incoming rain, making it a natural weather indicator. This sensitivity demonstrates the plant's remarkable response to atmospheric conditions. [source]
Traditional Herbal Use
MedicinalHistorically used in traditional medicine for digestive and skin conditions, though modern evidence is limited. The entire plant was historically prepared as a tea, though safety and efficacy require caution. [source]
Pollinator Support
WildlifeThe open flowers attract bees, butterflies, and other beneficial insects, making it valuable for pollinator-supporting gardens. Self-seeding plants create naturalized patches beneficial for local ecosystems. [source]
Cut Flowers
CraftThe delicate stems and brilliant flowers work well in small floral arrangements and are prized for their bright color and fine texture. Pick in morning when flowers are fully open for longest vase life. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Scarlett Pimpernel is grown primarily for ornamental flowers rather than harvest. Pick flowers in early morning when fully open for fresh arrangements. Allow some flowers to mature and dry on plant to collect seeds for next year's sowing.
Fun Facts
- 🌱 Scarlett Pimpernel's flowers exhibit nyctinasty (sleep movements), closing at night and on cloudy days due to changes in turgor pressure in leaf cells—a mechanism so reliable it was historically used to predict weather.
- 🌱 The plant inspired the famous novel and character 'The Scarlet Pimpernel' by Baroness Emmuska Orczy, though the literary connection is somewhat ambiguous as the exact plant inspiration remains debated.
- 🌱 Scarlett Pimpernel is sometimes considered weedy in certain regions due to its prolific self-seeding habit, yet it remains cherished in cottage gardens and wildflower mixes for its charming blooms and historical significance.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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