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How to Grow Common Zinnia Benary's Giant

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Common Zinnia Benary's Giant

Zinnia elegans 'Benary's Giant'

flower

Benary's Giant is a premium zinnia cultivar renowned for its exceptionally large, fully double flowers that can reach 4-5 inches in diameter. These robust plants grow 24-36 inches tall with sturdy stems ideal for cutting gardens and arrangements. The variety produces abundant blooms in vibrant colors throughout summer and fall.

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

  1. Plant Common Zinnia Benary's Giant

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Common Zinnia Benary's Giant blooms

    Around Jul 1

    ≈ 75 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum; 8+ hours preferred for maximum blooms
💧
Water: Moderate watering; allow soil to dry slightly between waterings. Water at soil level to keep foliage dry and prevent powdery mildew. Provide 1-1.5 inches per week during dry spells.
📏
Spacing: 12 inches
📅
Days to maturity: 75-90 days from seed to first bloom
🌱
Planting depth: 0.25 inches (surface sow or barely cover seeds); press lightly into soil

Soil

Type: Well-draining loamy soil with moderate fertility
pH: 6.0-7.5
Amendments:
Compost or aged manure for organic matter Perlite or sand for improved drainage Balanced fertilizer (10-10-10 or similar)

Growing Zones

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Thrives in zones 3-11; grown as an annual in cooler climates

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

2-3 weeks

Tiny seedlings emerge with rounded cotyledons, developing first true leaves within 7-10 days. Growth is relatively slow initially.

Maintain soil moisture without waterlogging. Provide bright light (grow lights if indoors). Keep at 70-75°F. Thin seedlings to prevent crowding.

2

Vegetative

4-6 weeks

Plants develop multiple sets of true leaves and a branching structure. Stems elongate and become sturdy. No flowers yet; foliage is the focus.

Pinch off top 0.5 inches when plants are 6-8 inches tall to encourage bushier growth and more flower production. Gradually harden off if starting indoors. Fertilize every 2-3 weeks with balanced fertilizer.

3

Budding & Early Flowering

2-3 weeks

Flower buds begin forming at branch tips. First blooms emerge, initially smaller but quickly reaching full size. Plant continues to grow in height.

Deadhead spent flowers regularly to encourage continuous blooming. Maintain consistent moisture. Apply fertilizer every 2 weeks, shifting to lower nitrogen (higher phosphorus) formula to support flowering.

4

Peak Flowering

6-10 weeks

Plant reaches mature height of 24-36 inches and produces abundant 4-5 inch double flowers continuously. Multiple flower layers create full, pompon-like blooms.

Deadhead spent blooms promptly. Water deeply 1-2 times weekly. Support tall stems with stakes or cages if planted in windy locations. Monitor for pests and diseases.

5

Late Season & Decline

Until first frost

Flowering continues but gradually slows as temperatures cool in fall. Flowers may appear slightly smaller or take longer to fully open in cool weather.

Continue deadheading to extend season. Reduce watering frequency slightly. Plants typically decline with first frost (32°F). Leave stems if saving seeds.

Companion Planting

Plan your garden →

Plant with:

Salvia Dusty Miller Cosmos Marigold Sunflower Celosia Sedum Artemisia

Avoid planting near:

Beans (can compete for nutrients) Fennel (allelopathic interference)

Common Pests

  • Spray with strong water jet to dislodge; use miticide if severe. Improve air circulation. Avoid overhead watering which promotes their spread.

  • Ensure good air circulation; water at soil level only. Apply sulfur fungicide or neem oil at first sign. Remove affected leaves. Avoid overhead watering.

  • Use yellow sticky traps. Spray with insecticidal soap or neem oil. Encourage beneficial insects like ladybugs and parasitic wasps.

  • Spray with water to dislodge. Apply insecticidal soap or horticultural oil. Introduce ladybugs or lacewings for biological control.

  • Improve drainage and air circulation. Remove affected plant parts promptly. Avoid overhead watering. Use well-draining soil and don't overwater.

Uses

🍳

Edible flower garnish

Culinary

Zinnia petals are edible and add vibrant color and mild flavor to salads, desserts, and cocktails. The petals are sweet with a slightly peppery note. [source]

🏠

Cut flower arrangements

Household

Benary's Giant is exceptional as a cut flower due to its long stems, large blooms, and exceptional vase life (7-10 days). Perfect for floral arrangements, bouquets, and wedding floristry. [source]

🎨

Dried flowers for crafts

Craft

Fully open blooms can be dried for use in crafts, pressed flower arrangements, potpourri, and decorative displays. Dry in a dark, airy space away from direct sunlight to preserve color. [source]

🦋

Pollinator support

Wildlife

Zinnias are excellent sources of nectar and pollen for bees, butterflies, and other beneficial insects. The abundant blooms provide consistent food throughout the growing season. [source]

💊

Traditional herbal use

Medicinal

In traditional Chinese medicine and other herbal traditions, zinnia has been used to support respiratory health and reduce inflammation, 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

Begin harvesting flowers when petals are fully opened and the bloom shows good substance (firm to touch). Cut in early morning or evening when stems are most turgid. Use a sharp knife to cut stems at a 45-degree angle, harvesting at least 6 inches of stem length. Remove lower leaves that would sit below the waterline in a vase. Harvest regularly (every 2-3 days) to encourage continuous production. Flowers last 7-10 days in a vase with fresh water.

Fun Facts

  • 🌱 Benary's Giant was developed by the renowned German seed company Ernst Benary & Co. in the 1950s and remains one of the finest zinnia cultivars available today.
  • 🌱 Zinnias are native to Mexico and were brought to Europe in the 18th century; they were named after Johann Gottfried Zinn, an 18th-century botanist.
  • 🌱 Unlike many ornamental plants, zinnias actually thrive in hot weather and produce more flowers as temperatures rise, making them perfect for summer gardens.

Gardening Terms

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

Cultivar Deadhead Full Sun pH True Leaves
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