How to Grow Giant Flowered Zinnia 'Purple Prince'

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Giant Flowered Zinnia 'Purple Prince'

Zinnia elegans 'Purple Prince'

flower

Purple Prince is a tall, vigorous zinnia cultivar that produces massive, fully double blooms in deep purple-magenta colors, often reaching 4-5 inches in diameter. These striking flowers are excellent for cutting and arrange beautifully in bouquets, providing continuous blooms throughout the growing season. The plant grows 24-36 inches tall and is a favorite among gardeners for dramatic garden displays and floral arrangements.

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Example Giant Flowered Zinnia 'Purple Prince' timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Giant Flowered Zinnia 'Purple Prince'

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Giant Flowered Zinnia 'Purple Prince' blooms

    Around Jun 16

    ≈ 60 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Giant Flowered Zinnia 'Purple Prince' dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum (8+ hours preferred for maximum blooms)
💧
Water: Water deeply 1-2 times weekly; keep soil consistently moist but not waterlogged. Reduce watering frequency once established. Avoid overhead watering to prevent mildew.
📏
Spacing: 12 inches
📅
Days to maturity: 60-75 days from seed to first blooms
🌱
Planting depth: 1/4 inch for seeds; transplants planted at same depth as container

Soil

Type: Well-draining loamy soil with moderate fertility
pH: 6.0-7.5
Amendments:
compost aged manure perlite or sand for drainage

Growing Zones

Find your zone →

Thrives in zones 3-11; treated as annual in cooler zones

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b

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Growth Stages

1

Seedling

2-3 weeks

Tiny seedlings with cotyledons emerge within 7-10 days. First true leaves develop quickly.

Provide bright light and keep soil consistently moist. Thin seedlings to prevent crowding. Maintain 70-75°F temperature.

2

Vegetative

3-4 weeks

Rapid growth with multiple sets of true leaves developing. Plant becomes bushy with increasingly thick stems.

Once true leaves appear, reduce watering frequency slightly. Begin fertilizing weekly with balanced fertilizer. Pinch the growing tip when plant is 6 inches tall to encourage bushier branching.

3

Pre-flowering

2-3 weeks

Plant reaches full height (24-36 inches). Flower buds begin forming at branch tips.

Provide sturdy support stakes or cages as plant gains height. Switch to phosphorus-rich fertilizer to encourage flowering. Continue consistent watering.

4

Flowering

8-12 weeks or until frost

Large, fully double purple-magenta flowers (4-5 inches) bloom abundantly. Multiple flowers per branch appear in succession.

Deadhead spent flowers regularly to encourage continuous blooming. Water consistently. Fertilize every 2-3 weeks with balanced or bloom-promoting formula.

5

Senescence/End of Season

Variable, until first hard frost

Flowering slows as temperatures cool in fall. Plant may decline with frost.

Allow final flowers to mature if saving seeds. Remove plant after frost. Compost healthy plant material.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

fennel potatoes

Common Pests

  • Increase humidity with regular misting. Use insecticidal soap or neem oil. Spray undersides of leaves. Remove heavily infested leaves.

  • Ensure good air circulation. Avoid overhead watering. Apply sulfur dust or fungicidal spray at first signs. Remove infected foliage.

  • Spray with strong water stream to dislodge. Use insecticidal soap or neem oil. Encourage beneficial insects like ladybugs.

  • Use yellow sticky traps. Spray with neem oil or insecticidal soap. Remove heavily infested leaves.

  • Improve drainage and air circulation. Avoid overwatering. Remove and destroy infected plants. Sterilize tools between cuts.

Uses

🍳

Edible flower garnish

Culinary

Zinnia petals are edible with a slightly peppery flavor and can be used as a colorful garnish for salads, cakes, and cocktails. [source]

🏠

Cut flower arrangements

Household

Purple Prince zinnias are exceptional cut flowers that last 7-10 days in a vase, providing dramatic color to floral displays and arrangements. [source]

🏠

Dried flowers

Household

These zinnias dry beautifully when hung upside-down in a warm, dry location, perfect for long-lasting dried arrangements and craft projects. [source]

🦋

Pollinator support

Wildlife

Zinnias attract butterflies, bees, and other pollinators throughout the growing season, making them valuable for supporting garden ecosystems. [source]

🎨

Pressed flowers

Craft

The large, flat double blooms press beautifully between heavy books and can be used in bookmarks, scrapbooking, and other craft projects. [source]

Harvest Tips

Cut flowers in early morning when stems are fully hydrated, at least 6 inches from base. Remove lower leaves below the waterline. Cut fresh daily for longest vase life (7-10 days). Deadhead spent blooms on growing plants regularly to maximize flowering throughout season. For seed saving, allow some flowers to dry on plant in late season; collect seed heads when papery and brown.

Fun Facts

  • 🌱 Zinnias were first domesticated by the Aztecs in Mexico and were named after the German botanist Johann Gottfried Zinn.
  • 🌱 Purple Prince and other giant zinnias produce their largest flowers when deadheaded regularly; removing spent blooms can increase flower size by up to 20%.
  • 🌱 Zinnias are one of the easiest flowers to grow from seed and reliably self-seed, providing new plants the following year if seeds are left to mature.

Gardening Terms

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

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