How to Grow Amaryllis Double Diamond

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Amaryllis Double Diamond

Hippeastrum × hybridum 'Double Diamond'

flower

Amaryllis Double Diamond is a spectacular hybrid bulb producing large, showy double flowers with white petals and deep red striping or picotee edges. This cultivar is prized for its dramatic, ruffled blooms and is commonly grown as a potted houseplant or in garden beds in warm climates. The double flowers are more abundant and longer-lasting than single-flowered varieties.

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Example Amaryllis Double Diamond timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Amaryllis Double Diamond

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. First Amaryllis Double Diamond blooms

    Around May 17

    ≈ 30 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Amaryllis Double Diamond dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily; bright indirect light acceptable indoors
💧
Water: Water moderately when soil surface becomes dry. During growing season, keep soil consistently moist but not waterlogged. Reduce watering during dormancy period. Avoid wetting the bulb crown to prevent rot.
📏
Spacing: 6-12 inches
📅
Days to maturity: 30-60
🌱
Planting depth: Plant bulb with top third exposed above soil surface

Soil

Type: Well-draining potting soil or sandy loam
pH: 6.0-7.0
Amendments:
Perlite or coarse sand for drainage Compost or aged manure for organic matter Bone meal or phosphorus-rich fertilizer

Growing Zones

Find your zone →

Thrives in zones 9-11; grown as a potted houseplant in cooler zones

9a 9b 10a 10b 11a 11b

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Growth Stages

1

Dormancy

8-12 weeks

Bulb is at rest with minimal visible growth. Foliage may be absent or dry.

Store in cool, dry location (50-60°F). Water sparingly. This rest period is essential for flowering.

2

Sprouting & Early Growth

2-3 weeks

Shoots emerge from bulb top, followed by long, strap-like green leaves. Flower stem(s) begin to develop.

Move to warm location (70-75°F) and begin regular watering. Place in bright light. Apply balanced fertilizer weekly.

3

Bud Formation

2-3 weeks

Flower buds form at the tip of the stem, initially appearing as small green or reddish bumps. Foliage continues to expand.

Maintain consistent warmth and moisture. Provide bright light and continue weekly fertilizing. Support tall stems with stakes if needed.

4

Flowering

2-4 weeks

Large, double flowers with white petals and red striping unfold sequentially along the stem. Each stem produces 2-4 blooms.

Reduce fertilizer to avoid excessive foliage. Maintain even moisture. Enjoy blooms for 2-3 weeks. Keep away from direct heat sources.

5

Post-Flowering & Dormancy Preparation

4-8 weeks

Flowers fade and drop. Foliage continues to photosynthesize and nourish the bulb. Gradually reduce watering.

Continue light feeding with diluted fertilizer to strengthen bulb for next season. Allow foliage to die back naturally. Once leaves yellow, cease watering and move to cool, dark storage.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Plants requiring frequent overhead watering Competing root systems in pots Damp-loving plants like hostas

Common Pests

  • Remove affected bulbs; treat soil with insecticidal granules; inspect bulbs before planting

  • Spray with insecticidal soap or neem oil; isolate infested plants; wipe leaves with alcohol-soaked cloth

  • Increase humidity; spray with neem oil or water; use miticide if severe

  • Hand-remove; spray with horticultural oil; apply systemic insecticide if needed

  • Maintain high humidity; spray with water forcefully; use miticide for severe infestations

Uses

🍳

Not typically culinary

Culinary

Amaryllis bulbs are toxic and should not be consumed. This plant is grown purely for ornamental purposes. [source]

🏠

Stunning cut flowers and floral arrangements

Household

The large, dramatic double blooms make exceptional, long-lasting cut flowers for vases and arrangements. A single stem can fill a room with visual impact and serve as a focal point in floral designs. [source]

🏠

Premium potted houseplant

Household

Amaryllis Double Diamond is widely grown as an indoor potted plant, especially around the winter holidays. Forcing amaryllis bulbs indoors is a popular seasonal gardening project that produces reliable, showy blooms. [source]

🦋

Pollinator attraction

Wildlife

The vibrant red and white flowers attract hummingbirds and other pollinators in gardens and outdoor settings, providing a nectar source during blooming season. [source]

🎨

Ornamental garden focal point

Craft

In warm climates, amaryllis thrives as a garden perennial, providing dramatic height and color to landscape designs. The architectural form of the flowers makes them prized by garden designers. [source]

Harvest Tips

Cut flower stems when first bud begins to open, using a clean knife. Cut at an angle above the bulb foliage. Place in clean vase with fresh, cool water. Change water every 2-3 days. Blooms typically last 2-3 weeks in a vase. Alternatively, allow blooms to open on the plant for sustained color in the garden or home.

Fun Facts

  • 🌱 Amaryllis Double Diamond bulbs can be forced to bloom indoors in just 4-6 weeks without soil in clear glass vases filled with pebbles and water, a technique dating back to Victorian parlor gardening.
  • 🌱 The name 'Amaryllis' is often used interchangeably with Hippeastrum, though true amaryllis is a different genus native to South Africa; Hippeastrum species are native to Central and South America.
  • 🌱 A single amaryllis bulb can produce multiple flower stems over consecutive years with proper care, with some bulbs living and blooming for 20+ years or more as multi-generational houseplants.

Gardening Terms

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

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