How to Grow Zinnia 'Benary's Giant'

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Zinnia 'Benary's Giant'

Zinnia elegans 'Benary's Giant'

flower

Benary's Giant is a premium zinnia cultivar prized for producing exceptionally large, fully double flowers reaching 4-5 inches in diameter on tall, sturdy stems. This variety is a favorite of florists and cut flower growers for its long vase life, vibrant color range, and prolific blooming throughout the season. It grows as an upright annual with excellent disease resistance compared to other zinnia varieties.

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

Plant Zinnia 'Benary's Giant'
Around Apr 17

Near Pittsburgh's average last spring frost.
Tend & protect
Late spring–summer

Watering, feeding, and pest-watch reminders.
First Zinnia 'Benary's Giant' blooms
Around Jun 16

≈ 60 days after planting

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

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum (8+ hours optimal for best flowering)

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Water: Water regularly and deeply, keeping soil consistently moist but not waterlogged. Provide 1-2 inches per week. Reduce watering slightly once established. Avoid overhead watering to minimize powdery mildew risk.

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Spacing: 12 inches

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Days to maturity: 60-80 days from seed to first flowers

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Planting depth: 1/4 inch; press seeds lightly into soil, keep moist until germination

Soil

Type: Well-draining loamy soil with moderate fertility

pH: 6.0-7.5

Amendments:

Compost or aged manure for organic matter Perlite for improved drainage Balanced fertilizer (10-10-10 or similar)

Growing Zones

Find your zone →

Thrives in zones 2-11; best performance in zones 5-10

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

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Growth Stages

Seedling

10-14 days

Tiny green cotyledons emerge, followed by true leaves. Plant is low to ground with fragile stems.

Maintain consistent moisture without waterlogging. Provide bright light (avoid leggy growth). Keep at 70-75°F optimal temperature. Thin seedlings to proper spacing.

Vegetative

3-4 weeks

Plant grows rapidly in height with branching. Stems become sturdy and woody. Leaves are lance-shaped, slightly rough textured. No flowers yet.

Pinch back growing tips when 4-6 inches tall to encourage bushier growth and more flower stems. Apply balanced fertilizer every 2-3 weeks. Ensure adequate light and spacing for air circulation.

Budding

2-3 weeks

Flower buds form at branch tips, visible as tight green knobs. Stems are fully developed and strong.

Continue regular watering and fertilizing (transition to higher phosphorus to encourage blooming). Remove any diseased leaves. Ensure good air circulation around base.

Flowering

6-10 weeks (until frost)

Large, fully double pompom-like flowers bloom in vibrant colors (red, pink, orange, yellow, white, bicolor). Multiple flower heads per stem.

Deadhead spent flowers regularly to promote continuous blooming. Water consistently. Apply high-phosphorus fertilizer every 2 weeks. Cut flowers in early morning for longest vase life (7-14 days).

Seed Production

2-3 weeks after flowering ends

If flowers are left on plant, they fade and develop seed heads. Seeds mature inside papery brown bracts.

Allow select flowers to mature for seed saving. Harvest seed heads when dry and brown. Store seeds in cool, dry place for next season.

Companion Planting

Plan your garden →

Plant with:

Basil Marigold Cosmos Cleome Sedum Rudbeckia Salvia Celosia

Avoid planting near:

Fennel (allelopathic; inhibits growth of nearby plants) Root crops in same bed (competition for resources)

Common Pests

Improve air circulation with proper spacing. Avoid overhead watering. Apply sulfur dust or neem oil at first sign. Select resistant varieties when possible.
Use yellow sticky traps. Spray with insecticidal soap or neem oil. Remove heavily infested leaves. Encourage beneficial insects like ladybugs.
Increase humidity with regular misting. Spray leaves with strong water jet. Apply miticide or insecticidal soap. Avoid over-fertilizing with nitrogen.
Spray with water to dislodge. Use insecticidal soap or neem oil. Release ladybugs or lacewings. Yellow sticky traps help monitoring.
Ensure excellent drainage. Avoid overwatering. Remove infected plants. Do not compost diseased material. Improve air circulation.

Uses

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Edible petals for garnish

Culinary

Zinnia petals are edible and add vibrant color and mild, slightly citrusy flavor to salads, cakes, and cocktails. Use only ornamental varieties grown without pesticides. [source]

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Premium cut flowers

Craft

Benary's Giant is prized by florists and home arrangers for its exceptional vase life (7-14 days), large perfect blooms, and sturdy stems that hold up well in arrangements. The variety is superior to standard zinnias for professional and wedding floral design. [source]

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Garden color from summer to frost

Household

Provides continuous, prolific blooming in red, pink, orange, yellow, white, and bicolor combinations from mid-summer through first frost. Creates a dramatic impact in beds and borders with minimal maintenance. [source]

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Pollinator magnet

Wildlife

Attracts bees, butterflies, and beneficial insects throughout the growing season. Despite being a double flower, many pollinators can access the blooms, supporting garden ecosystem health. [source]

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Traditional herbal properties

Medicinal

Zinnia species have been used in traditional medicine (particularly in India and China) for anti-inflammatory and wound-healing properties, though scientific evidence is limited. The plant may have mild antimicrobial compounds. [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 fully open but petals still firm. Cut stems at 45-degree angle just above a leaf node to encourage branching. Place immediately in cool water with floral preservative. Recut stems and change water every 2-3 days for 7-14 day vase life. Remove lower leaves that would sit in water. For seed saving, allow select flowers to dry on plant until seed heads are brown and papery; harvest and dry further indoors for 2-3 weeks before storing.

Fun Facts

🌱 Benary's Giant was developed in Germany by the prestigious Benary seed company and remains a gold standard zinnia variety nearly a century later, still used extensively in commercial cut flower production.
🌱 Zinnias are native to Mexico and are named after Johann Gottfried Zinn, an 18th-century botanist and entomologist who died of dysentery—an ironic tribute to a plant that has become a beloved garden staple.
🌱 Deadheading zinnias (removing spent flowers) can literally double or triple your flower production throughout the season, as the plant is evolutionarily driven to produce seeds—removing flowers 'tricks' it into making more.

Gardening Terms

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

Annual Cultivar Deadhead Full Sun pH Pinch Back True Leaves

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