How to Grow Midnight Blue
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Midnight Blue
Ipomoea purpurea 'Midnight Blue'
vineMidnight Blue is a stunning morning glory variety featuring deep indigo to purple-blue flowers that open in the early morning and close by afternoon. This vigorous climbing vine grows quickly and produces abundant blooms throughout the summer and fall. It's an excellent choice for trellises, arbors, and fences, adding vertical interest and color to garden spaces.
When should you plant Midnight Blue in your zone?
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Example Midnight Blue timeline · Pittsburgh, PA (Zone 6b)
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Plant Midnight Blue
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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Harvest Midnight Blue
Around Jun 6≈ 50 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Midnight Blue dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-11; annual in cooler climates, can reseed or perennialize in warmer zones
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Get my Midnight Blue timeline →Growth Stages
Germination
7-14 daysSeeds sprout and produce initial cotyledons (seed leaves). Growth is slow initially.
Keep soil consistently moist but not waterlogged. Provide warm temperatures (65-75°F ideal). Nick seeds or soak overnight before planting to speed germination.
Seedling & Early Growth
2-3 weeksTrue leaves emerge; plants develop thin, delicate stems. Growth accelerates as temperatures warm.
Provide support structure or stake early. Ensure good light to prevent leggy growth. Thin seedlings to recommended spacing. Begin hardening off if starting indoors.
Vegetative Growth
3-4 weeksVigorous vine elongation with multiple branches; abundant heart-shaped green foliage. Stems climb quickly and vine can grow 6-10 feet or more.
Guide vines onto support structure (trellis, arbor, fence). Pinch back early growth to encourage bushiness if desired. Water regularly. Fertilize sparingly; excess nitrogen promotes foliage over flowers.
Flowering
8-12 weeks (summer through fall frost)Spectacular deep indigo-purple trumpet-shaped flowers bloom profusely. Flowers open in early morning and close in afternoon/on cloudy days. Blooming continues through fall until frost.
Maintain consistent watering. Deadheading spent flowers can encourage more blooms, though it's labor-intensive. Reduce nitrogen fertilization. Continue supporting vine growth.
Seed Production & Maturation
Variable; continues until frostIf flowers are not deadheaded, small round seed pods develop containing 1-4 seeds each. Pods dry on the vine as frost approaches.
Allow some flowers to go unpollinated if you want seeds for next season. Collect seed pods before hard frost. Dry indoors and store in cool, dry place. In warmer zones, plant can self-sow.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with water to dislodge; use insecticidal soap or neem oil if severe. Increase humidity around plants.
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Use yellow sticky traps; spray with insecticidal soap or neem oil. Remove heavily infested leaves.
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Remove by hand; use beer traps or copper barriers. Apply diatomaceous earth around base.
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Strong water spray; insecticidal soap; neem oil; encourage beneficial insects like ladybugs.
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Ensure good air circulation. Spray with baking soda solution (1 tbsp per gallon water) or sulfur dust. Avoid overhead watering.
Uses
Edible flowers
CulinaryThe flowers are edible with a slightly sweet taste and can be used as garnishes for salads, desserts, and beverages. They add striking visual appeal to culinary presentations. [source]
Flower arranging & floral design
CraftThe vivid midnight blue flowers are popular in fresh floral arrangements, though their short bloom window (morning only) must be considered. Dried flowers and seed pods can also be used in dried arrangements. [source]
Garden ornamentation & screening
HouseholdMidnight Blue morning glories are ideal for creating living screens on fences, trellises, and arbors, providing quick coverage and stunning seasonal color. They can effectively hide unsightly structures. [source]
Pollinator attraction
WildlifeThe abundant flowers attract hummingbirds, bees, and other pollinators throughout the blooming season. Seed pods provide food for birds in fall and winter. [source]
Traditional herbal use
MedicinalMorning glory seeds contain lysergic acid amide (LSA) and have been used traditionally in various cultures for medicinal and spiritual purposes, though safety and legality vary by region. [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 flowers in early morning just after they open for longest vase life (though they close by afternoon). For seed collection, allow pods to mature and dry on vine until brown and papery, then harvest before hard frost. Store seeds in cool, dry location. Morning glories typically self-seed readily in warm climates.
Fun Facts
- 🌱 Morning glories got their name because their flowers reliably open at dawn and close by early afternoon, following a circadian rhythm independent of light levels.
- 🌱 Midnight Blue morning glory seeds are notably hard-coated and benefit from scarification (scratching or nicking the seed coat) or overnight soaking to break dormancy and improve germination rates.
- 🌱 Morning glories are prolific self-seeders and can return year after year in warm climates; in temperate zones they behave as true annuals and won't overwinter unless protected.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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