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How to Grow Agapanthus Storm Cloud

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Agapanthus Storm Cloud

Agapanthus africanus 'Storm Cloud'

flower

Agapanthus Storm Cloud is a stunning ornamental flowering plant featuring deep blue-purple flowers arranged in large spherical umbels atop tall stems. This cultivar is prized for its dramatic dark coloring and long blooming period, making it a striking focal point in borders, containers, and landscape designs.

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Example Agapanthus Storm Cloud timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Agapanthus Storm Cloud

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Agapanthus Storm Cloud blooms

    Mid-to-late summer

    Before the first fall frost (≈ Nov 8)

Sample dates for Pittsburgh, PA. Sign up to get exact Agapanthus Storm Cloud dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily; tolerates light afternoon shade in hot climates
💧
Water: Moderate watering during growing season; allow soil to dry somewhat between waterings. Reduce watering in winter when dormant. Drought tolerant once established.
📏
Spacing: 18-24 inches
📅
Days to maturity: 120-150 days to first flowers from transplant; typically flowers in summer of second year
🌱
Planting depth: Crown level for established plants; seeds sown surface to 1/8 inch depth

Soil

Type: Well-draining loamy or sandy soil
pH: 6.0-7.0
Amendments:
Compost Peat moss or coconut coir Perlite for drainage

Growing Zones

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Thrives in zones 8b-11; can be grown in zone 8a with winter protection

8b 9a 9b 10a 10b 11

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Growth Stages

1

Seedling/Establishment

6-12 months

Young plants develop long, strap-like green leaves in clumps with minimal flowering

Keep soil consistently moist but not waterlogged. Protect from extreme cold. Do not expect flowers in first year.

2

Vegetative Growth

6-12 months

Plant develops increasingly larger clumps of long, arching foliage with multiple growth points

Water regularly during growing season. Feed monthly with balanced fertilizer. Clumps should reach substantial size.

3

Budding

3-4 weeks

Tall flower stems emerge from the center of the clump with visible green buds forming at the apex

Continue regular watering. Increase potassium-rich fertilizer to encourage bud development. Stake if necessary in windy locations.

4

Flowering

6-8 weeks

Stunning deep blue-purple flowers open in dense spherical clusters (umbels) atop 24-36 inch stems

Maintain consistent moisture. Deadhead spent flowers to encourage extended blooming. Support tall stems if needed.

5

Seed Set & Dormancy

8-12 weeks

Flowers fade and seed pods develop; foliage begins to yellow as plant prepares for dormancy

Reduce watering gradually. Remove dead foliage in late fall/early winter. Leave seed heads for winter interest if desired.

Companion Planting

Plan your garden →

Plant with:

Salvia Coreopsis Rudbeckia Ornamental grasses Lavender Russian sage Catmint Sedums

Avoid planting near:

Competing deep-rooted perennials in small spaces Plants requiring consistently moist soil Aggressive spreaders like mint or bamboo

Common Pests

  • Increase humidity, spray with water, apply neem oil if severe

  • Remove with cotton swab dipped in alcohol, spray with insecticidal soap

  • and

    Hand-pick, use beer traps, apply copper barriers or food-grade diatomaceous earth

  • Prune affected leaves, apply horticultural oil in dormant season

Uses

🍳

Not edible

Culinary

Agapanthus is purely ornamental and not consumed. All parts may cause skin irritation in sensitive individuals. [source]

🎨

Cut flowers and arrangements

Craft

The striking deep blue-purple flower spheres are excellent for fresh floral arrangements, adding dramatic color and architectural form. They also dry well for dried arrangements. [source]

🦋

Pollinator attraction

Wildlife

Agapanthus flowers attract bees, butterflies, and other beneficial insects, supporting pollinator populations in the garden. [source]

🏠

Landscape focal point

Household

The bold dark blue flower clusters and architectural foliage make Agapanthus Storm Cloud an excellent specimen plant for borders, containers, and contemporary garden designs. [source]

💊

Traditional herbal use

Medicinal

In traditional African medicine, Agapanthus has been used for various purposes, though modern evidence is limited and consultation with herbalists is recommended. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Agapanthus is grown for ornamental flowers rather than harvest. Cut flowers for arrangements when most umbel florets have opened; they last 1-2 weeks in a vase. Leave some flowers on the plant for wildlife. Deadhead spent flowers to prolong blooming season.

Fun Facts

  • 🌱 The name 'Agapanthus' comes from Greek words 'agape' (love) and 'anthos' (flower), literally meaning 'flower of love'
  • 🌱 The 'Storm Cloud' cultivar earned its name from the dramatically deep blue-purple flowers that resemble storm clouds against the sky
  • 🌱 Agapanthus can live for decades in the right conditions, with mature clumps becoming increasingly spectacular over time

Gardening Terms

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

Cultivar Deadhead Full Sun pH
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