How to Grow Northern Star
Northern Star
Ipomoea purpurea 'Northern Star'
vineNorthern Star is a stunning morning glory cultivar featuring deep purple-blue flowers with distinctive white star-shaped markings in the center. This fast-growing annual vine reaches 8-10 feet tall and produces abundant blooms throughout the growing season. It's prized for its ornamental appeal and ability to quickly cover trellises, arbors, and vertical structures.
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Example Northern Star timeline · Pittsburgh, PA (Zone 6b)
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Plant Northern Star
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 Northern Star
Around Jun 6≈ 50 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Northern Star dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives nationwide as a warm-season annual; best performance in zones 3-10
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Seedling
2-3 weeksTiny heart-shaped cotyledons emerge, followed by small true leaves. Plant is delicate and low-growing.
Keep soil moist but not soggy. Provide bright indirect light if starting indoors. Thin to strongest seedlings once true leaves appear.
Vegetative Growth
3-4 weeksRapid vine growth with increasingly larger heart-shaped leaves. Plant develops multiple stems and begins climbing its support structure.
Provide sturdy trellis or support structure immediately. Water regularly and fertilize every 2-3 weeks with balanced fertilizer. Pinch growing tips if bushy growth is desired.
Flowering
6-10 weeksAbundant funnel-shaped flowers with distinctive white star patterns on deep purple-blue petals emerge along the vines. Flowers open in early morning and close by afternoon.
Continue regular watering and fertilizing with lower nitrogen formula to promote blooms. Remove spent flowers to encourage continued flowering. Support vines with twine or clips as needed.
Peak Bloom
4-6 weeksPlant is completely covered with flowers during warm weather. Multiple flower clusters open daily, creating stunning visual display.
Maintain consistent moisture. Water deeply once or twice weekly. Deadhead if desired, though not necessary. Watch for pest infestations.
Seed Development
3-4 weeks until seeds are viableAfter flowers fade, papery seed pods form along the vines. These round pods contain 3-4 seeds each.
Allow pods to dry on the vine if collecting seeds for next season. Pods will turn brown and papery when mature. Harvest before fall frost.
Common Pests
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Hand-pick in early morning, use row covers on young plants, or apply neem oil spray. Beetle traps placed nearby can reduce populations.
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Spray foliage with water to dislodge, increase humidity, apply insecticidal soap or neem oil. Improve air circulation to prevent infestations.
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Use yellow sticky traps, spray with insecticidal soap, or apply neem oil. Remove heavily infested leaves.
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Remove by hand, use copper tape barriers, apply diatomaceous earth around base, or set beer traps.
Uses
Vertical Garden Beauty
HouseholdNorthern Star morning glories are exceptional for creating living screens, covering unsightly structures, and adding height and color to gardens. Their rapid growth makes them ideal for quickly establishing privacy or shade on trellises and arbors. [source]
Cut Flower Arrangements
CraftThe striking purple-blue flowers with white star centers are excellent for fresh flower arrangements, though they close by afternoon. Cut stems in early morning when flowers are fully open for best display. [source]
Pollinator Attraction
WildlifeNorthern Star flowers attract hummingbirds, bees, and other pollinators throughout the growing season, providing essential nectar sources and supporting garden biodiversity. [source]
Edible Flowers
CulinaryWhile not commonly eaten, morning glory flowers are technically edible and can be used as garnish in salads or desserts for their visual appeal and mild, slightly sweet flavor. Use only pesticide-free flowers. [source]
Harvest Tips
Northern Star is primarily grown for ornamental flowers rather than harvest. However, if collecting seeds for next season, allow seed pods to mature and dry on the vine until papery, typically 3-4 weeks after flowering. Harvest pods in late summer or early fall before frost kills the plant. Store dried seeds in cool, dry conditions. Seeds typically germinate better after soaking in warm water for 24 hours before spring planting.
Fun Facts
- 🌱 Morning glories are called 'morning' glories because their flowers open at dawn and typically close by early afternoon on sunny days. Cloudy days can keep blooms open longer.
- 🌱 Northern Star seeds are incredibly hard-coated and benefit from scarification (lightly scratching the seed coat) or overnight soaking in warm water to improve germination rates.
- 🌱 Morning glories can climb by twining their stems around support structures and can grow 1-2 feet per week under ideal conditions, making them among the fastest-growing annual vines.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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