How to Grow Zinnia, Benary's Giant White

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Zinnia, Benary's Giant White

Zinnia elegans 'Benary's Giant White'

flower

Benary's Giant White is a tall, robust zinnia cultivar producing enormous double flowers with pure white petals on strong stems. This variety is prized by florists and gardeners for its impressive 4-5 inch blooms and excellent cut flower longevity. It grows vigorously to 24-36 inches tall and flowers prolifically throughout summer and fall.

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

  1. Plant Zinnia, Benary's Giant White

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Zinnia, Benary's Giant White blooms

    Around Jun 26

    ≈ 70 days after planting

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

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum; 8+ hours preferred for maximum blooms
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Water: Water deeply and consistently, keeping soil evenly moist but not waterlogged. Provide 1-1.5 inches weekly through rainfall or irrigation. Mulch around plants to retain moisture and regulate temperature. Reduce watering slightly once established, but maintain consistent moisture during flowering.
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Spacing: 18 inches
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Days to maturity: 70-90 days from seed to first bloom
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Planting depth: Surface sow or barely cover seeds (1/8 inch); press seeds lightly into soil. Transplants should be set at soil line depth.

Soil

Type: Well-draining loamy to sandy loam soil
pH: 6.0-7.5
Amendments:
Compost or aged manure for soil enrichment Perlite or coarse sand if soil compacts easily Balanced slow-release fertilizer incorporated at planting

Growing Zones

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Thrives in zones 3-11; grown as annual in cool climates, may persist in warm zones

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 emerged seedlings with first true leaves appearing within 7-10 days. Growth is slow initially.

Keep soil consistently moist but not soggy to prevent damping off. Provide bright light (grow lights 3-4 inches above seedlings). Thin overcrowded seedlings when first true leaves emerge. Maintain 70-75°F soil temperature.

2

Vegetative Growth

3-4 weeks

Rapid stem and leaf development with increasingly robust plant structure. Multiple stems branch from main trunk. Plants reach 6-12 inches tall indoors or after hardening off.

Harden off seedlings by gradually exposing to outdoor conditions over 7-10 days before transplanting. Space properly to ensure air circulation. Pinch off the top growing tip when plants are 6 inches tall to encourage bushier, branching form. Keep soil evenly moist.

3

Flower Initiation & Bud Formation

3-4 weeks

Main stems and lateral branches elongate to full height (24-36 inches). Flower buds begin forming at stem tips. Plant becomes visibly sturdier with thicker stems.

Provide sturdy support or staking for tall plants, especially if in windy locations or with heavy blooms. Begin weekly fertilization with balanced or bloom-boosting formula (10-10-10 or similar). Monitor for powdery mildew in humid conditions; ensure good air circulation.

4

Flowering & Blooming

8-12 weeks or until frost

Large 4-5 inch fully double white flowers open sequentially on strong stems. Blooms are pristine white with fully filled double petals. Continuous flowering occurs as lower flowers are deadheaded.

Deadhead spent flowers regularly to promote continuous blooming and redirect energy into new flowers. Water consistently; stress from irregular watering reduces bloom quality. Continue fertilizing every 7-10 days. Cut flowers for arrangements in early morning when stems are turgid; they last 7-10 days in a vase.

5

Seed Production & Senescence

Variable; ends at first hard frost or in warm zones may persist through mild winter

If flowers are not deadheaded, seed pods develop. Plant vigor gradually declines as frost approaches. In warm zones, bloom may continue into fall.

Allow a few flowers to set seed if you wish to collect seed for next year. Save mature seed pods (let dry on plant), extract seeds, and store in cool, dry conditions. In frost-prone areas, plants typically end when temperatures drop below 50°F consistently.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Dill Beans

Common Pests

  • Spray with strong water jet to dislodge; use insecticidal soap or neem oil if severe. Increase humidity around plants. Ensure adequate spacing for air circulation.

  • Provide excellent air circulation, avoid overhead watering. Apply sulfur-based fungicide or baking soda spray (1 tablespoon per gallon water with spreader-sticker). Remove heavily affected leaves.

  • Spray with insecticidal soap or neem oil. Attract natural predators like ladybugs with companion plants. Strong water spray can dislodge small populations.

  • Use yellow sticky traps to monitor and capture adults. Spray neem oil or insecticidal soap on leaf undersides. Ensure good air circulation.

  • and (Rhizoctonia, Pythium spp.)

    Avoid overwatering and waterlogging; ensure well-draining soil. Improve air circulation. Remove and discard infected plants. Sterilize tools. Do not reuse soil from infected plants.

Uses

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Edible flower garnish

Culinary

Zinnia petals are edible with a slightly spicy flavor and can be used as a colorful garnish for salads, desserts, and cocktails. While white zinnias are visually striking, ensure they are grown without pesticides if intended for consumption. [source]

🏠

Premium cut flowers for arrangements

Household

Benary's Giant White is a florist-grade variety ideal for wedding bouquets, arrangements, and formal events due to its large pristine blooms and long vase life. The pure white color pairs well with nearly any other flower color and makes an excellent filler or focal flower. [source]

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Dried flowers for crafts

Craft

Zinnia blooms dry well and retain their structure and color for months. Hang-dry flowers in a dark, well-ventilated location for use in dried arrangements, wreaths, and craft projects. [source]

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Pollinator support

Wildlife

Zinnias attract bees, butterflies, and other beneficial insects to the garden. The abundant nectar and pollen-rich flowers make them an excellent plant for supporting pollinator populations throughout summer and fall. [source]

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Traditional herbal applications

Medicinal

Zinnias have been used in traditional Chinese and Ayurvedic medicine. Flower infusions and extracts have been studied for anti-inflammatory and antioxidant properties, though scientific validation is ongoing. [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 cutting flowers in early morning when stems are fully hydrated. Cut just as outer petals begin to unfurl for maximum vase life (7-10 days). Cut stems at a 45-degree angle and immediately place in clean water with flower preservative. Remove leaves below the waterline to prevent rot. Cut flowers promote additional blooming on remaining plant.

Fun Facts

  • 🌱 Benary's Giant is a classic German heirloom variety developed in the early 20th century by the renowned Benary seed company in Erfurt, Germany, and remains one of the tallest and largest-flowered zinnia cultivars available.
  • 🌱 Zinnias were first domesticated by the Aztecs and have been cultivated for over 500 years; they are the national flower of Mexico.
  • 🌱 This cultivar's impressive double flowers contain dozens of perfectly arranged petals created through selective breeding to enhance the plant's natural tendency to produce full blooms, making each flower a botanical masterpiece.

Gardening Terms

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