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How to Grow Benary's Giant Zinnia

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Benary's Giant Zinnia

Zinnia elegans 'Benary's Giant'

flower

Benary's Giant is a stunning tall zinnia cultivar prized for its large, fully double flowers that can reach 4-5 inches in diameter. These vigorous plants grow 24-36 inches tall and produce abundant blooms in a wide range of vibrant colors throughout the growing season. Perfect for cut flowers, borders, and cottage gardens, these zinnias are beloved by florists and gardeners alike.

Looking for a specific variety?

Benary's Giant Scarlet Benary's Giant Coral Benary's Giant Lavender Benary's Giant Pink Benary's Giant Yellow Benary's Giant Purple

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Example Benary's Giant Zinnia timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Benary's Giant Zinnia

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Benary's Giant Zinnia blooms

    Around Jun 16

    ≈ 60 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Benary's Giant Zinnia dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily (8+ hours preferred for maximum blooms)
💧
Water: Regular watering, 1-1.5 inches per week; keep soil consistently moist but not waterlogged. Drought-tolerant once established but flowers larger with consistent moisture.
📏
Spacing: 12 inches
📅
Days to maturity: 60-75 days from seed to first flowers
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Planting depth: Plant seeds 0.25 inches deep; transplants at same depth as nursery container

Soil

Type: Well-draining loamy soil
pH: 6.0-7.0
Amendments:
Compost aged manure perlite for drainage balanced fertilizer

Growing Zones

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Thrives in zones 2-11 as an annual; handles heat and humidity exceptionally well

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

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Growth Stages

1

Seedling

7-14 days

Cotyledons emerge, followed by true leaves. Plants are small and delicate with soft stems.

Maintain consistent moisture and provide bottom heat (70-75°F) for germination. Keep soil evenly moist but not soggy. Provide bright light once sprouted.

2

Vegetative Growth

3-4 weeks

Rapid stem and leaf expansion; plants become bushy with multiple branching points. No buds visible yet.

Pinch back when plants reach 6-8 inches tall to encourage bushier growth and more flowers. Gradually harden off transplants before outdoor planting. Water regularly and fertilize with balanced fertilizer every 2-3 weeks.

3

Bud Formation & Flowering

4-6 weeks until first blooms

Terminal buds appear at branch tips and develop into characteristic large double flowers. Plants reach full size (24-36 inches).

Continue regular watering and deadheading spent flowers to encourage continuous blooming. Switch to lower-nitrogen, higher-phosphorus fertilizer to promote flowering. Stake tall varieties if in windy locations.

4

Peak Blooming

8-10 weeks (until frost)

Abundant 4-5 inch double flowers in full color; multiple flowers per plant simultaneously. Plant reaches maximum height and fullness.

Deadhead regularly (remove spent flowers) to extend bloom season. Water at soil level to prevent foliar diseases. Continue fertilizing every 2-3 weeks. Harvest flowers in early morning for best vase life.

5

Late Season & Frost Sensitivity

Until first frost

Plants continue blooming but slow as temperatures drop. Frost will kill plants (frost-tender annual).

Enjoy blooms until first frost. Save seeds from best flowers by allowing some blooms to fully mature and dry on plant. Plant dies at first hard frost (28°F or below).

Companion Planting

Plan your garden →

Plant with:

Salvia marigolds cosmos dahlias celosia dusty miller ornamental grasses sunflowers

Avoid planting near:

Black walnut trees (juglone toxicity to all zinnias)

Common Pests

  • Spray with water to dislodge; use neem oil or insecticidal soap if severe. Ensure adequate humidity (they prefer dry conditions).

  • Hand-pick early morning when beetles are less active. Use pheromone traps away from plants or apply neem oil spray.

  • Improve air circulation; avoid overhead watering. Spray with sulfur or potassium bicarbonate fungicide if needed. Remove affected leaves.

  • Yellow sticky traps; spray with insecticidal soap or neem oil. Remove heavily infested leaves.

  • No cure; remove infected plants. Control leafhoppers with neem oil or insecticidal soap to prevent spread.

Uses

🍳

Edible Flowers & Garnish

Culinary

Zinnia petals are edible with a slightly peppery flavor and are commonly used to garnish salads, desserts, and drinks. They add striking color and mild flavor to fresh cuisine. [source]

🎨

Cut Flowers & Floral Arrangements

Craft

Benary's Giant zinnias are florist-quality cut flowers prized for their large, full double blooms and long vase life. They are among the most popular zinnia varieties for professional and home flower arranging. [source]

🏠

Home Decoration & Bouquets

Household

The abundant, vibrant blooms make stunning indoor arrangements and are excellent for both casual bouquets and formal centerpieces. Available in pink, red, orange, yellow, white, purple, and bicolors. [source]

🦋

Pollinator Support

Wildlife

Zinnias attract bees, butterflies, and hummingbirds throughout the growing season. They are an excellent nectar source for beneficial insects and support pollinator populations. [source]

🎨

Dried Flowers & Seed Saving

Craft

Large zinnia flowers dry well for dried arrangements and craft projects. Allow mature flowers to dry on the plant, then save seeds for next season's planting. [source]

Harvest Tips

Cut flowers in early morning when stems are fully hydrated for best vase life (7-10 days). Cut stems at 45-degree angle just above a leaf node. Deadhead spent flowers on growing plants to encourage continuous blooming throughout the season. Cut stems 6-12 inches long for arrangements.

Fun Facts

  • 🌱 Benary's Giant zinnias were developed by German seed company Ernst Benary in the early 1900s and remain one of the most popular zinnia cultivars over a century later.
  • 🌱 Zinnias are native to Mexico and have been cultivated for centuries; the Aztecs called them 'xochiquetzal' (flower of pride).
  • 🌱 Benary's Giant produces hundreds of flowers per plant over a season when deadheaded regularly, making it incredibly productive compared to ornamental varieties.

Gardening Terms

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

Annual Cultivar Deadhead Full Sun Germination pH Pinch Back Transplant True Leaves
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