How to Grow Scarlet Monkeyflower
iNaturalist
Scarlet Monkeyflower
Mimulus cardinalis
flowerScarlet monkeyflower is a vibrant perennial wildflower native to western North America, known for its brilliant red-orange tubular flowers that attract hummingbirds and other pollinators. It thrives in moist, shaded environments and blooms prolifically from late spring through fall. This stunning native plant adds dramatic color to riparian gardens, shade borders, and water garden edges.
When should you plant Scarlet Monkeyflower in your zone?
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Example Scarlet Monkeyflower timeline · Pittsburgh, PA (Zone 6b)
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Plant Scarlet Monkeyflower
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 Scarlet Monkeyflower blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Scarlet Monkeyflower dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Best grown in USDA zones 8-10; can be challenging in cooler zones but may survive as an annual or with winter protection in zone 7
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Seedling
3-4 weeksTiny seedlings with 2-4 true leaves; very delicate and slow-growing initially
Maintain high humidity and consistent moisture without waterlogging. Keep under lights 12-14 hours daily if starting indoors. Do not allow soil to dry out.
Vegetative Growth
4-6 weeksPlant develops trailing or mounding form with soft green foliage; no flowers yet. Stems become more robust.
Pinch back growing tips to encourage bushiness and branching. Maintain consistent moisture and partial shade. Begin fertilizing weekly with balanced or bloom-promoting fertilizer.
Budding & Early Flowering
2-3 weeksFlower buds appear along stem tips; first red-orange tubular flowers begin to open
Continue deadheading spent flowers to encourage continuous blooming. Maintain consistent watering. Reduce nitrogen fertilizer if available; increase phosphorus and potassium.
Peak Flowering
6-12 weeks or longer with proper carePlant is covered with vibrant scarlet-red tubular flowers with contrasting spots; extremely attractive to hummingbirds
Deadhead regularly to extend blooming season. Keep soil consistently moist. Watch for spider mites in very hot, dry conditions. Provide afternoon shade in temperatures above 85°F.
Post-Bloom/Senescence
Variable; dormancy or decline periodFlowering slows in late fall or after extended heat; foliage may fade. Plant may go dormant or decline in winter (zone-dependent)
In mild climates, cut back old stems by 1/3 to encourage fresh growth and rebloom. In cold areas, treat as annual or bring indoors. Reduce watering but maintain some moisture.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Increase humidity with regular misting; spray with water to dislodge. Use neem oil or sulfur spray if infestation is severe. Ensure adequate shade in hot climates.
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Spray with strong stream of water; apply insecticidal soap or neem oil. Introduce ladybugs or lacewings for biological control.
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Use yellow sticky traps to monitor and control. Apply neem oil or pyrethrin-based insecticide. Improve air circulation.
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Ensure excellent drainage; avoid waterlogging. Do not crowd plants. Remove affected plants. Improve air circulation. Use well-draining soil amendments.
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Improve air circulation; avoid wetting foliage. Apply sulfur powder or potassium bicarbonate fungicide. Remove heavily infected leaves.
Uses
Hummingbird Magnet
WildlifeThe brilliant red tubular flowers are irresistible to hummingbirds and other nectar-feeding birds. The flower shape and color are specifically adapted to attract these pollinators, making it an excellent choice for wildlife gardens. [source]
Cut Flowers & Floral Arrangements
CraftThe long-lasting, vibrantly colored flowers make excellent additions to fresh floral arrangements and bouquets. Stems can be cut regularly for indoor display without harming the plant. [source]
Edible Flowers
CulinaryThe flowers are edible with a mild, slightly sweet flavor and are used as garnishes in salads and on desserts. They add vibrant color to culinary presentations. [source]
Traditional Native American Uses
MedicinalNative American tribes historically used Mimulus species for treating wounds and minor ailments, though modern medicinal applications are limited. [source]
Garden Landscaping & Water Features
HouseholdPerfect for shaded borders, riparian gardens, rain gardens, pond edges, and other moist landscape areas where its vibrant color adds significant visual impact. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Scarlet monkeyflower is not harvested for consumption. Cut stems for fresh floral arrangements by pinching or cutting just above a leaf node in the early morning when stems are turgid. Deadhead spent flowers regularly throughout the blooming season to promote continuous flowering and prevent self-seeding.
Fun Facts
- 🌱 The common name 'monkeyflower' refers to the flowers' resemblance to a monkey's face, with the spotted throat looking like a grinning mouth.
- 🌱 Scarlet monkeyflower is native to streams and springs in California and adjacent western regions, and has been used by Native Americans for centuries in traditional medicine.
- 🌱 Hummingbirds are so strongly attracted to this flower that it has evolved specifically to bloom at the same time as peak hummingbird migration, providing critical nectar resources for the birds.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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