How to Grow Midnight Conversion

Midnight Conversion

Ipomoea purpurea 'Midnight Conversion'

vine

Midnight Conversion is a stunning morning glory cultivar featuring deep purple-black flowers with distinctive white or pale pink stripes radiating from the center. This fast-growing annual vine produces large, heart-shaped leaves and prolific blooms throughout the growing season. It's a vigorous climber perfect for trellises, arbors, and garden structures.

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

  1. Plant Midnight Conversion

    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 Conversion

    Around Jun 6

    ≈ 50 days after planting

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

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily for best flowering
💧
Water: Moderate water needs; keep soil evenly moist but not waterlogged. Water at the base to avoid fungal issues. Reduce watering once established, as morning glories are somewhat drought-tolerant.
📏
Spacing: 6-12 inches
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Days to maturity: 50-70 days to first flowers
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Planting depth: 0.25-0.5 inches for seeds; plant transplants at same depth as container

Soil

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

Growing Zones

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Thrives in zones 3-11 as an annual; can self-seed readily in warm climates

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

7-14 days

Cotyledons emerge and initial heart-shaped true leaves develop. Seedlings are tender and delicate.

Keep soil warm and consistently moist. Provide bright indirect light if starting indoors. Harden off gradually before transplanting outdoors.

2

Vegetative Growth

3-4 weeks

Rapid vine elongation with multiple heart-shaped leaves emerging. Plant establishes a strong root system and climbs vigorously up supports.

Provide sturdy trellis or support structure early. Water regularly but allow soil to dry slightly between waterings. Pinch tips if bushier growth is desired.

3

Budding & Early Flowering

2-3 weeks

Flower buds form at leaf axils. First flowers appear, showcasing the dramatic purple-black petals with white striping.

Maintain consistent moisture and full sun exposure. Reduce nitrogen fertilizer to promote flowering over foliage. Remove any damaged leaves.

4

Peak Flowering

6-8 weeks or until frost

Abundant blooms open each morning and close by afternoon. Flowers display vibrant color contrast and create stunning visual impact.

Continue regular watering at the base. Deadheading spent flowers is optional but can encourage slightly more blooms. Monitor for pests.

5

Seed Development & Season End

Until first frost

Flowers fade as seed pods develop. Vines continue growth until first frost kills the plant in cold climates.

Allow some flowers to remain for seed development if you want self-seeding next year. Water moderately. In late season, reduce supplemental watering to harden off the plant.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Beans Peas Carrots

Common Pests

  • Hand-pick in early morning, use row covers when young, apply neem oil or insecticidal soap as needed

  • Spray with water to dislodge, use neem oil, maintain adequate humidity

  • Yellow sticky traps, insecticidal soap, neem oil, increase air circulation

  • Remove affected leaves, spray with neem oil or horticultural oil in early morning

  • and (Gastropoda)

    Hand-pick at night, use slug baits, create copper barriers, encourage natural predators

Uses

🍳

Traditional Asian cooking ingredient

Culinary

Morning glory leaves and shoots (known as water spinach or kangkong when young) are eaten as a nutritious green vegetable in Asian cuisines, typically stir-fried. The tender shoots are valued for their slightly bitter flavor and crunchy texture. [source]

💊

Traditional herbal remedy

Medicinal

In traditional Chinese and Ayurvedic medicine, morning glory seeds and roots have been used to support digestive health and overall wellness. The seeds contain alkaloids that have been studied for their bioactive properties. [source]

🏠

Floral arrangements and cut flowers

Household

The striking dark purple flowers with white striping make exceptional fresh cut flowers for arrangements, though they close in the afternoon. Harvest in early morning for longest vase life. [source]

🎨

Garden design and aesthetic landscaping

Craft

Perfect for creating dramatic vertical interest, screening unsightly views, or adorning pergolas and trellises with its vigorous vining growth and stunning flower color contrast. Often used in cottage garden and contemporary garden designs. [source]

🦋

Pollinator support

Wildlife

The abundant flowers attract hummingbirds, bees, and butterflies throughout the blooming season, making it valuable for supporting pollinator populations in gardens. [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 primarily ornamental; harvest flowers for fresh arrangements in early morning when they first open. If saving seeds, allow pods to fully dry on the vine until brown and papery, then collect before they shatter.

Fun Facts

  • 🌱 Morning glory flowers open in the early morning and typically close by afternoon, a phenomenon controlled by the plant's internal circadian rhythm and response to light and temperature changes.
  • 🌱 Midnight Conversion produces seeds naturally and can self-seed prolifically in warm climates, returning year after year without replanting, though seedlings may have variable flower colors.
  • 🌱 The vines can grow 8-10 feet or more in a single season, making them among the fastest-growing annual ornamental plants for quick garden coverage.

Gardening Terms

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

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