How to Grow Dahlia Mignon

Dahlia Mignon

Dahlia × pinnata 'Mignon'

flower

Dahlia Mignon is a compact, dwarf dahlia variety prized for its abundant, fully double flowers and bushy growth habit. Reaching only 12-18 inches tall, it produces prolific blooms in vibrant colors throughout summer and fall, making it ideal for containers, borders, and cut flowers. This tender perennial is typically grown as an annual in temperate climates.

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Example Dahlia Mignon timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Dahlia Mignon

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Dahlia Mignon blooms

    Around Jun 16

    ≈ 60 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily for best flowering
💧
Water: Water consistently, keeping soil evenly moist but not waterlogged. Water at soil level to avoid wetting foliage. Reduce watering in fall as growth slows.
📏
Spacing: 12 inches
📅
Days to maturity: 60-70 days
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Planting depth: Tubers: 2 inches deep; seeds: 1/4 inch deep

Soil

Type: Well-draining loamy soil rich in organic matter
pH: 6.0-6.8
Amendments:
Compost Aged manure Peat moss or coco coir Perlite for container drainage

Growing Zones

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Thrives in zones 8-11; grow as tender annual in colder zones

8a 8b 9a 9b 10a 10b 11a 11b

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Growth Stages

1

Sprouting

2-3 weeks

Tubers or seedlings emerge with initial leaves appearing above soil. Growth is slow in first 2-3 weeks.

Keep soil warm (65-70°F) and moist. Provide light once shoots emerge. Handle tubers gently to avoid rot.

2

Vegetative Growth

3-4 weeks

Plant develops bushy foliage with multiple stems and a rounded, compact form. Leaves are pinnately lobed and green.

Pinch off growing tips when 6 inches tall to encourage bushiness. Maintain consistent moisture and regular feeding every 2 weeks with balanced fertilizer.

3

Budding

2-3 weeks

Flower buds begin to form at stem tips. Buds are tight and green initially, gradually enlarging.

Continue fertilizing, but switch to lower-nitrogen formula to encourage blooming. Remove any diseased foliage. Ensure adequate sun exposure.

4

Flowering

6-10 weeks

Fully double, pompom-like flowers in various colors (red, pink, orange, yellow, white, purple) bloom abundantly. Flowers measure 2-3 inches across.

Deadhead spent blooms regularly to encourage continuous flowering. Support stems with stakes if needed. Keep watering consistent even during blooming.

5

Late Season & Dormancy

4-6 weeks until frost

Flowering slows as temperatures cool in fall. In zones 8-11, foliage may die back with first frost; tubers enter dormancy underground.

In cold zones, dig tubers before hard frost, dry thoroughly, and store in cool (50-60°F), dark place. In warm zones, cut back after frost and mulch heavily.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Garlic Onions Potatoes

Common Pests

  • Spray leaves with water to dislodge; use neem oil or insecticidal soap if severe. Increase humidity around plants.

  • Ensure good air circulation; avoid overhead watering. Apply sulfur dust or potassium bicarbonate fungicide if needed.

  • Spray with strong water stream; use insecticidal soap or neem oil. Encourage beneficial insects like ladybugs.

  • and

    Remove by hand, especially at dusk. Use beer traps or copper tape barriers. Apply diatomaceous earth around plant base.

  • Hand-pick in early morning; use pheromone traps away from plants. Avoid insecticides that harm pollinators.

  • Ensure excellent drainage; avoid overwatering. Use well-draining soil; improve aeration. Remove affected plants to prevent spread.

Uses

🍳

Edible Flowers for Garnish

Culinary

Dahlia petals are edible with a slightly sweet flavor and can be used to garnish salads, desserts, and cocktails. They add visual appeal and a delicate, floral note to culinary presentations. [source]

🎨

Cut Flowers & Floral Arrangements

Craft

Dahlia Mignon's compact size and prolific blooms make it excellent for fresh flower arrangements, bouquets, and floral design. Long vase life (7-10 days) and abundant flowers throughout the season provide consistent material for cutting. [source]

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Container & Landscape Beauty

Household

The dwarf, bushy habit makes it perfect for containers, window boxes, borders, and small garden spaces. Massed plantings create dramatic color displays. [source]

🦋

Pollinator Attraction

Wildlife

Dahlia flowers attract bees, butterflies, and other pollinators throughout the growing season. Providing a valuable nectar source for beneficial insects supporting garden biodiversity. [source]

💊

Traditional Herbal Use

Medicinal

In some traditional medicine systems, dahlia tubers have been used to support digestive health and as an inulin source. Modern research is exploring potential prebiotic applications. [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 hydrated and blooms are fully open but still firm. Cut at a 45-degree angle with sharp, clean pruners. Strip lower leaves and immediately place stems in cool water. Change water every 2-3 days. Deadheading spent flowers (pinching off just below flower head) prolongs blooming season by 4-6 weeks.

Fun Facts

  • 🌱 Dahlia Mignon is a result of decades of breeding to create a compact version of larger dahlia varieties, with the first 'Mignon' cultivars introduced in the 1990s.
  • 🌱 The genus Dahlia is named after the 18th-century Swedish botanist Anders Dahl and is Mexico's national flower, with tubers having been cultivated by the Aztecs for food and ceremonial purposes.
  • 🌱 Dahlias are classified by flower form into multiple categories (decorative, pompom, ball, waterlily, etc.), with Mignon typically being a pompom or ball type, characterized by their fully double, rounded blooms.

Gardening Terms

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