How to Grow Larkspur Astolat
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Larkspur Astolat
Delphinium elatum 'Astolat'
flowerLarkspur Astolat is a striking hybrid delphinium cultivar known for its tall spikes of semi-double flowers in shades of pink, mauve, and purple with dark eyes. This dramatic perennial or biennial reaches heights of 4-6 feet and blooms profusely in early to mid-summer. It's a favorite for cut flowers and cottage gardens, requiring cool climates and careful attention to growing conditions.
When should you plant Larkspur Astolat in your zone?
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Example Larkspur Astolat timeline · Pittsburgh, PA (Zone 6b)
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Plant Larkspur Astolat
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 Larkspur Astolat blooms
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Larkspur Astolat dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Zones 2-7; thrives in cool climates and struggles in hot, humid summers
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Get my Larkspur Astolat timeline →Growth Stages
Seed Germination
7-14 daysTiny seedlings emerge with true leaves appearing after cotyledons
Keep soil moist and temperature cool (60-65°F); provide bright indirect light; thin seedlings to prevent crowding
Vegetative Growth
4-8 weeksRosette of deeply lobed, fern-like foliage develops; plant establishes strong root system
Harden off transplants gradually; water regularly; apply balanced fertilizer every 3-4 weeks; stake early if planting is not sheltered
Bud Formation
2-3 weeksTall flower spikes emerge from leaf axils with tightly closed flower buds clustered along the stem
Install sturdy stakes or support cages; maintain consistent moisture; avoid overhead watering to prevent powdery mildew; apply dilute fertilizer with higher phosphorus content
Flowering
3-4 weeksSemi-double flowers open progressively from bottom to top along the spike in pink, mauve, or purple shades with dark centers
Dead-head spent flowers to encourage branching and extended blooming; provide wind protection; stake stems securely; water at soil level only
Seed Maturation & Decline
4-6 weeksFlowers fade; seed pods form along the spike; foliage may decline in late summer heat
Allow some flowers to remain for seed collection if desired; remove spent stalks in late fall; provide cool temperatures and supplemental water if growing as perennial
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Increase humidity with regular misting; spray with neem oil or horticultural soap; provide afternoon shade in hot climates
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Ensure good air circulation; water at soil level only; apply sulfur dust or baking soda solution; thin crowded foliage
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Handpick in early morning; apply copper barriers; use slug pellets or beer traps; remove debris and dense groundcover
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and
(fungal)
Ensure excellent drainage; avoid waterlogging; plant in raised beds in humid regions; remove affected plants immediately
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and
(fungal)
Remove infected leaves promptly; improve air circulation; avoid overhead watering; apply fungicide in early stages
Uses
Culinary flowers (garnish only)
CulinaryFresh Larkspur Astolat flowers can be used as edible garnish for gourmet presentations; ensure flowers have not been treated with pesticides or florist chemicals. [source]
Cut flowers and floral design
CraftOne of the finest cut flower delphiniums; exceptional for tall arrangements, wedding bouquets, and dramatic centerpieces; excellent longevity in water. [source]
Traditional herbal use
MedicinalHistorical use in folk medicine, though modern use is limited due to toxicity concerns; not recommended for consumption without professional guidance. [source]
Drying and preservation
HouseholdFlower spikes dry beautifully when hung upside down in a cool, dark space; used in dried arrangements and craft projects for months. [source]
Pollinator attraction
WildlifeTall flower spikes attract bumblebees, butterflies, and hummingbirds throughout the blooming season, providing valuable nectar sources. [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 flower spikes in early morning when buds are just opening or when flowers are partially open for longest vase life (7-10 days). Cut stems at least 12 inches long using sharp pruners. For seed collection, allow flowers to fade and seed pods to dry on the plant; harvest pods when brown and dry, then store in cool, dry location. Deadhead regularly to encourage reblooming and prevent self-seeding.
Fun Facts
- 🌱 The cultivar name 'Astolat' references the legendary Lady of Astolat from Arthurian legend (Idyll of the King), reflecting the flower's romantic, storybook elegance
- 🌱 Delphinium flowers contain toxic alkaloids that have been used historically as natural pesticides and insecticides; all parts of the plant are poisonous if ingested
- 🌱 Larkspur blooms follow the pattern of opening flowers from the base of the spike upward, allowing a single spike to produce flowers over 3-4 weeks and making it ideal for progressive flowering in arrangements
Gardening Terms
New to gardening? Learn about terms used in this guide:
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