How to Grow Couleur Cardinal

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Couleur Cardinal

Dahlia × hybrida 'Couleur Cardinal'

flower

Couleur Cardinal is a stunning dahlia cultivar prized for its deep crimson-red blooms with rich burgundy undertones. This decorative dahlia produces full, multi-petaled flowers that reach 4-6 inches in diameter, making it a showstopper in any garden. It's a popular choice for cut flowers and ornamental garden displays.

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Example Couleur Cardinal timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Couleur Cardinal

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Couleur Cardinal blooms

    Around Jun 26

    ≈ 70 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Couleur Cardinal dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum
💧
Water: Consistent moisture during growing season; water 1-2 inches per week. Allow soil surface to dry slightly between waterings. Reduce watering in fall as plants prepare for dormancy.
📏
Spacing: 24-36 inches
📅
Days to maturity: 70-90 days from planting tubers to first bloom
🌱
Planting depth: 4-6 inches deep for tubers; plant eye/bud facing upward

Soil

Type: Well-draining loamy soil with organic matter
pH: 6.0-7.0
Amendments:
compost aged manure peat moss perlite for drainage

Growing Zones

Find your zone →

Thrives in zones 7-10; treat as annual or lift tubers in cooler zones

7a 7b 8a 8b 9a 9b 10a

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Growth Stages

1

Sprouting

2-3 weeks

Tubers develop sprouts and shoots emerge from soil

Plant after last frost when soil is warm (60°F+). Water gently until shoots appear. Keep soil consistently moist but not waterlogged.

2

Vegetative Growth

4-6 weeks

Tall stems with compound green foliage develop; plant may reach 3-4 feet tall

Pinch off center stem when plant reaches 12 inches tall to encourage bushy growth. Install stakes or cages for support. Apply balanced fertilizer every 2-3 weeks.

3

Budding

2-3 weeks

Flower buds appear at stem tips; buds gradually enlarge and show color

Switch to lower-nitrogen, higher-phosphorus fertilizer to promote flowering. Continue deadheading adjacent smaller buds to direct energy to main flowers. Maintain consistent watering.

4

Flowering

8-12 weeks

Full, multi-petaled cardinal-red blooms with burgundy tones open to 4-6 inches diameter

Deadhead spent flowers regularly to encourage continuous blooming. Cut stems in early morning for fresh arrangements. Monitor for pests and diseases. Continue regular watering and feeding.

5

Senescence & Tuber Development

4-8 weeks until frost

Flowering slows; foliage yellows as plant energy moves to tuber storage

Reduce watering as temperatures cool. Stop fertilizing. After first light frost, lift tubers carefully, cure in cool dry place for 1-2 weeks, then store in cool (45-50°F), dry location over winter.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

fennel potatoes tomatoes

Common Pests

  • Hand-pick beetles early morning; use row covers; apply neem oil or pyrethrin insecticide; consider Japanese beetle traps placed away from dahlias

  • Spray with strong water stream; apply insecticidal soap; use neem oil; introduce ladybugs or lacewings

  • Increase humidity by misting; spray with water; apply miticide or neem oil; encourage predatory mites

  • and (Gastropoda)

    Remove by hand at dusk; use copper barriers; apply diatomaceous earth; set beer traps; use iron phosphate bait

  • Ensure good air circulation; avoid overhead watering; apply sulfur dust or fungicide; remove affected leaves

Uses

🍳

Edible Garnish

Culinary

Dahlia petals are edible with a slightly sweet, peppery flavor and add visual drama to salads, desserts, and cocktails. [source]

🎨

Cut Flower Arrangements

Craft

The cardinal-red, full-petaled blooms are prized by florists and gardeners for dramatic fresh and dried arrangements, bouquets, and special occasion decorations. [source]

🏠

Garden Display & Ornamental

Household

Couleur Cardinal creates a stunning focal point in borders, beds, and containers, adding depth of color and texture to garden landscapes. [source]

🦋

Pollinator Support

Wildlife

The abundant blooms attract bees, butterflies, and other pollinators, supporting local ecosystems and promoting biodiversity. [source]

💊

Traditional Wellness

Medicinal

In some traditional practices, dahlia flowers and roots have been used in herbal remedies, though scientific evidence is limited. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Cut flowers in early morning when stems are fully hydrated, using sharp scissors or pruning shears. Cut at a 45-degree angle just above a leaf node. Remove lower leaves below the waterline. Recut stems and change water every 2-3 days. Blooms last 7-10 days in a vase. For tuber harvesting in fall, wait until foliage is blackened by frost, dig carefully to avoid damaging tubers, cure in cool place, then store over winter.

Fun Facts

  • 🌱 Dahlias originated in Mexico and were considered sacred by the Aztecs, who used tubers as a food source and flowers in ceremonies.
  • 🌱 Couleur Cardinal's name means 'Cardinal Color' in French, referring to the distinctive deep crimson-red hue resembling a cardinal's plumage.
  • 🌱 Dahlias are the national flower of Mexico and come in nearly every color except true blue; they can produce hundreds of blooms per plant over a season with proper deadheading.

Gardening Terms

New to gardening? Learn about terms used in this guide:

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