How to Grow Ball's Double Blue
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Ball's Double Blue
Delphinium × cultorum 'Ball's Double Blue'
flowerBall's Double Blue is a stunning cultivar of garden delphinium featuring fully double, sky-blue flowers densely packed on tall, dramatic spikes. These perennial flowers are prized for their striking vertical architecture and rich blue coloring, making them excellent as cut flowers and garden focal points. They typically grow 4-6 feet tall and bloom in early to mid-summer.
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Example Ball's Double Blue timeline · Pittsburgh, PA (Zone 6b)
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Plant Ball's Double Blue
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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First Ball's Double Blue blooms
Around Jul 16≈ 90 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Ball's Double Blue dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 3-6, with success possible in zones 2-7 with proper care
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Get my Ball's Double Blue timeline →Growth Stages
Seedling
3-4 weeksSmall cotyledons emerge; true leaves develop with distinctive deeply lobed margins characteristic of delphiniums
Provide consistent moisture and bright light. Keep soil warm (65-75°F for germination). Thin seedlings to prevent damping off.
Vegetative/Establishment
6-8 weeksPlant develops a strong root system and bushy foliage with dissected, fern-like leaves. Height increases steadily.
Water regularly, feed with balanced fertilizer every 3-4 weeks. Install support stakes early to prevent wind damage. Pinch tips at 12 inches tall to encourage branching.
Budding
2-3 weeksFlower spikes emerge from leaf axils. Dense clusters of buds form and begin to show color (blue).
Increase phosphorus and potassium through fertilizer; reduce nitrogen to avoid excess foliage. Ensure stakes are secure. Remove lower foliage if air circulation is poor.
Flowering
4-6 weeksSpectacular double blue flowers open sequentially along spike from bottom to top, creating a long display of densely-packed florets
Continue staking and support. Deadhead spent flowers to extend bloom. Water at soil level only. Watch for powdery mildew and treat promptly if needed.
Post-bloom/Senescence
4-8 weeks until fall dormancyFlowers fade and dry; seed pods develop. Foliage may yellow. Plant begins to decline in energy.
Cut back spent spikes if you want a second flush of smaller flowers in fall. Leave some seed heads for wildlife or collection. Tidy up foliage to reduce disease pressure.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Remove affected leaves promptly; use insecticidal soap; encourage parasitoid wasps by planting diverse flowering plants nearby
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and
Handpick, use copper tape around plant bases, apply organic slug baits, encourage ground beetles
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Increase humidity and water spray, use neem oil spray, ensure good air circulation
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Avoid overhead watering, improve air circulation, apply sulfur or baking soda spray at first sign, remove affected foliage
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Remove damaged flowers, spray insecticidal soap, encourage beneficial predatory insects
Uses
Exceptional cut flower and floral arrangements
HouseholdBall's Double Blue delphiniums are highly prized by florists and flower arrangers for their stunning vertical spikes, rich blue color, and long vase life. They add dramatic height and structure to wedding bouquets, garden arrangements, and formal displays. [source]
Pollinator attraction
WildlifeThe abundant double flowers attract bees, hummingbirds, and other beneficial insects to the garden. While double flowers may offer less nectar than singles, the extended bloom period provides important mid-summer resources. [source]
Pressed flowers and dried arrangements
CraftThe individual florets press beautifully and retain their blue color well when dried. Used in dried arrangements, pressed flower art, and botanical crafts. [source]
Historical herbal use
MedicinalTraditional herbalism has utilized delphinium species for various remedies, though modern use is limited due to plant toxicity. Historical records document use as an insecticide and for skin treatments. [source]
Ornamental garnish (non-toxic confirmation required)
CulinaryWhile some delphinium species contain toxic alkaloids, certain ornamental cultivars have been used cautiously as garnishes in formal cuisine. Only use if sourced from trusted suppliers confirming safety and absence of chemical treatments. [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 stems for arrangements in the morning when fully hydrated, cutting just below the lowest open flower. Recut stems and use flower preservative for longer vase life (7-10 days). For seed saving, allow flower spikes to dry on plant; collect pods when they turn brown and papery, then air-dry further before extracting seeds.
Fun Facts
- 🌱 Ball's Double Blue is named after the Ball Seed Company, a historic seed breeding powerhouse founded in 1888. This cultivar represents decades of selective breeding for the perfect double-flowered delphinium.
- 🌱 Delphiniums have been cultivated for over 400 years and were favorite subjects of old master painters and Renaissance tapestries; the name 'delphinium' comes from the Greek word for dolphin, as the flower's nectary was thought to resemble the marine mammal.
- 🌱 The double flowers of this cultivar are sterile (producing no viable seed), which means they typically don't self-sow in gardens and require propagation by division or cuttings to preserve the exact variety.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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