How to Grow Midnight Hour

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Midnight Hour

Ipomoea purpurea 'Midnight Hour'

vine

Midnight Hour is a stunning variety of morning glory with deep purple, nearly black flowers that bloom in profusion throughout the growing season. This vigorous annual vine climbs quickly and produces heart-shaped foliage, making it an excellent choice for trellises, arbors, and garden structures. The dramatic dark blooms open in the morning and close by afternoon, creating a fleeting but spectacular daily display.

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Example Midnight Hour timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Midnight Hour

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Midnight Hour

    Around Jun 6

    ≈ 50 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Midnight Hour dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum
💧
Water: Moderate watering; allow soil to dry slightly between waterings. Avoid overwatering, which reduces flowering. Water at soil level to prevent fungal issues.
📏
Spacing: 12-18 inches
📅
Days to maturity: 50-70 days from seed to first blooms
🌱
Planting depth: 0.5 inches

Soil

Type: Well-draining loamy soil
pH: 6.0-7.0
Amendments:
Compost peat moss perlite for drainage

Growing Zones

Find your zone →

Thrives in zones 2-11 as an annual; hardy perennial in zones 9-11

2a 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

Small plants with 2-4 true leaves and delicate stems

Keep soil consistently moist but not waterlogged. Provide bright indirect light. Thin seedlings to prevent overcrowding. Consider scarifying seeds or soaking overnight before planting to improve germination.

2

Vegetative Growth

3-4 weeks

Vines rapidly produce heart-shaped leaves and begin climbing or trailing

Install support structure early (trellis, stake, or arbor). Water regularly as plant establishes. Pinch back tips if bushier growth is desired. Fertilize with balanced fertilizer every 2-3 weeks.

3

Budding

1-2 weeks

Small flower buds form along the vines

Maintain consistent watering and sunlight. Reduce nitrogen fertilizer to encourage flowering over leaf production. Watch for early pests.

4

Flowering

6-10 weeks (continuous until frost)

Abundant deep purple, nearly black trumpet-shaped flowers open each morning

Provide adequate water and full sun. Deadhead spent flowers if desired (though not necessary). Continue light fertilizing with phosphorus-rich formula. Flowers open early morning and close by afternoon.

5

Seed Development & Decline

Until first frost

After flowering, seed pods form; plant dies back after first frost

Allow some flowers to set seed if you want self-sowing next year. In warm zones, plant may produce seeds viable for next season. Collect seeds before frost if desired.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Pole beans (competition for space) Other vigorous vines that compete for nutrients

Common Pests

  • Spray with insecticidal soap or neem oil; encourage beneficial insects like ladybugs

  • Increase humidity by misting; spray with neem oil or miticide if severe

  • Use yellow sticky traps; spray with insecticidal soap or neem oil

  • Hand-pick in early morning; use pheromone traps away from garden; apply neem oil

Uses

🦋

Pollinator Attraction

Wildlife

The abundant flowers attract bees, butterflies, and hummingbirds, making Midnight Hour an excellent choice for supporting pollinator populations throughout the growing season. [source]

🏠

Garden Architecture & Screening

Household

Its rapid vine growth makes it perfect for quickly covering unsightly structures, creating privacy screens, or adding dramatic vertical interest to gardens, arbors, and trellises. [source]

🎨

Cut Flowers & Garden Display

Craft

The stunning dark purple flowers can be cut in early morning for flower arrangements, though they do close within hours. Better suited for viewing directly in the garden. [source]

💊

Traditional Herbal Uses

Medicinal

Morning glory seeds and roots have been used in traditional medicine systems, though they contain ergot alkaloids and should not be consumed without expert guidance. [source]

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

Harvest Tips

Morning glories are grown for their flowers, not for harvest in the traditional sense. Enjoy blooms by viewing them in early morning hours before they close. If collecting seeds for next season, allow flower pods to dry on the vine, then collect before frost and store in cool, dry place. Seeds remain viable for 2-3 years.

Fun Facts

  • 🌱 The name 'morning glory' refers to the flowers' habit of opening fresh each morning and closing by afternoon, creating a new display daily.
  • 🌱 Midnight Hour's deep purple color is so dark it appears almost black, making it one of the most dramatic morning glory varieties available.
  • 🌱 Morning glory seeds have a hard seed coat and benefit from scarification (scratching the surface) or overnight soaking to improve germination rates.

Gardening Terms

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

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