How to Grow Scarlet Flame Phlox
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Scarlet Flame Phlox
Phlox paniculata 'Scarlet Flame'
flowerScarlet Flame Phlox is a cultivar of garden phlox featuring vibrant red-orange flowers with a distinctive darker eye center, blooming in mid to late summer. This upright perennial reaches 24-36 inches tall and produces fragrant, showy flower clusters (panicles) that attract butterflies and hummingbirds. It's a reliable, long-blooming garden workhorse that returns year after year.
When should you plant Scarlet Flame Phlox in your zone?
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Example Scarlet Flame Phlox timeline · Pittsburgh, PA (Zone 6b)
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Plant Scarlet Flame Phlox
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 Flame Phlox blooms
Mid-to-late summerBefore the first fall frost (≈ Nov 8)
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Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 4-8, tolerates zone 3 with winter protection
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Seedling/Transplant Establishment
4-6 weeks indoors before transplantingYoung plants with 2-4 sets of true leaves, developing root systems
Keep soil consistently moist; avoid letting seedlings dry out; provide bright indirect light initially; transplant outdoors after last frost
Vegetative Growth
6-8 weeks in springUpright stems with elongated lance-shaped leaves, no flowers yet; plant reaches 12-18 inches
Pinch back growing tips in early season to encourage bushier, more compact growth; water regularly; apply light fertilizer mid-spring; thin crowded stems for air circulation
Bud Formation
2-3 weeksFlower buds appear at stem tips, forming tight clusters (panicles) before opening
Continue regular watering; increase fertilizer with low-nitrogen formulation to promote flowering; stake taller varieties if needed; remove any diseased leaves
Flowering
6-8 weeks (July through September in most zones)Abundant vibrant scarlet-red flowers with darker eye centers open in dense panicles; fragrant blooms attract butterflies and hummingbirds
Deadhead spent flower clusters regularly to extend bloom time; water during dry spells; monitor for powdery mildew in humid conditions; provide evening watering to prevent fungal issues
Seed Set & Dormancy
Autumn through early spring (dormant period 3-5 months)Flowers fade; seed pods develop if not deadheaded; foliage begins to yellow in fall; plant dies back to ground after first hard frost
Allow some flower heads to set seed for self-seeding or cut for seeds; remove dead foliage in fall or early spring; apply 2-3 inches of mulch for winter protection in colder zones; no watering needed after dormancy
Common Pests
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Improve air circulation; avoid wetting foliage; spray with sulfur or neem oil at first sign; plant in full sun with good drainage; apply preventive fungicide in humid conditions
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Increase humidity; spray with water to dislodge; use miticide if severe; reflective mulches may deter; encourage natural predators
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Remove and destroy infected stems; improve drainage; avoid overhead watering; thin crowded plants for air circulation; sterilize pruning tools
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Spray with strong water stream; use insecticidal soap; introduce beneficial insects like ladybugs; neem oil for heavier infestations
Uses
Edible Flower Garnish
CulinaryPhlox flowers are edible and add color and mild, slightly sweet flavor to salads, desserts, and beverages. Use petals fresh for garnishing cakes, salads, or crystallized for decorative cake accents. [source]
Cut Flowers & Arrangements
HouseholdScarlet Flame Phlox is excellent for fresh flower arrangements, bouquets, and garden displays. The fragrant, showy blooms last well in the vase and pair beautifully with complementary garden flowers. [source]
Pollinator Attraction
WildlifePhlox flowers are highly attractive to butterflies, hummingbirds, and other pollinators, making it invaluable for supporting gardens and ecosystems. The bright red-orange color and nectar-rich blooms are particularly favored by ruby-throated hummingbirds. [source]
Traditional Herbal Uses
MedicinalHistorically, phlox root was used in traditional Native American medicine for respiratory conditions and skin conditions. Modern herbalism occasionally uses dried flowers for their mild diaphoretic properties. [source]
Dried Flower Crafts
CraftPhlox flowers dry well and retain color reasonably when pressed or air-dried, making them suitable for dried arrangements, pressed flower crafts, and floral preservation projects. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Phlox is grown for ornamental flowers and fragrance rather than harvest. Cut flower stems in early morning when buds are opening for fresh arrangements; they last 7-10 days in a vase. Deadhead spent flower clusters regularly to encourage continuous blooming throughout the summer. Allow some flowers to remain on plants for seed production or natural self-seeding if desired.
Fun Facts
- 🌱 The name 'Phlox' comes from the Greek word meaning 'flame,' referencing the vibrant colors of the flowers—and Scarlet Flame's name is particularly fitting given its intense red-orange hue.
- 🌱 Phlox flowers are intensely fragrant, especially in the evening, and the scent is believed to be an adaptation to attract night-pollinating moths and insects.
- 🌱 Scarlet Flame Phlox can self-seed readily in the garden, allowing it to naturalize over time and create beautiful drifts of color in subsequent seasons.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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