How to Grow Blue Horizon
Wikimedia Commons
Blue Horizon
Ipomoea tricolor 'Blue Horizon'
vineBlue Horizon is a stunning morning glory cultivar prized for its large, vibrant sky-blue flowers that open in early morning and close by afternoon. This vigorous climbing vine produces heart-shaped foliage and abundant blooms throughout the growing season, making it an excellent choice for trellises, arbors, and vertical garden structures. It's a tender annual in most climates, thriving in warm conditions and full sunlight.
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Example Blue Horizon timeline · Pittsburgh, PA (Zone 6b)
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Plant Blue Horizon
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 Blue Horizon
Around Jun 6≈ 50 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Blue Horizon dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Best grown as an annual in zones 3-9; can overwinter in zones 10-11
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Seedling
2-3 weeksTiny heart-shaped cotyledons emerge, followed by first true leaves. Growth is slow initially.
Keep soil consistently moist but not soggy. Provide warm conditions (70°F+). Thin seedlings to strongest plants. Begin training to support structure early.
Vegetative Growth
3-4 weeksVigorous vine elongates with multiple stems and heart-shaped leaves developing. Plant begins climbing or spreading.
Install sturdy trellis or support. Train vines gently to desired direction. Water regularly. Fertilize every 2-3 weeks with balanced fertilizer.
Flowering
8-12 weeks until frostLarge, trumpet-shaped sky-blue flowers (2-3 inches wide) appear profusely along the vine, opening in early morning.
Maintain consistent watering. Deadhead spent flowers to encourage more blooms. Reduce nitrogen fertilizer; switch to lower-nitrogen formula to promote flowering over foliage.
Peak Bloom
4-8 weeks (or until first frost)Hundreds of bright blue flowers cover the vine, creating a stunning display. Flowers open fresh each morning.
Continue regular watering and maintenance. Support heavy, flower-laden vines if needed. Allow some flowers to go to seed if you want self-seeding next year.
Seed Development
3-4 weeksFlowers fade and dry seed pods develop. Foliage may thin slightly as plant diverts energy to seed production.
Stop deadheading if you want seeds for next year. Collect seed pods when they turn brown and papery. Plant is frost-sensitive and will die with first hard freeze.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Hand-pick in early morning, use row covers, apply neem oil or pyrethrin spray. Avoid beetles' preferred hours (10am-2pm).
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Spray with strong water stream to dislodge; apply insecticidal soap or neem oil every 5-7 days. Increase humidity.
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Use yellow sticky traps, spray undersides of leaves with insecticidal soap or neem oil weekly.
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Spray with water, use insecticidal soap, apply neem oil, or introduce ladybugs and lacewings.
Uses
Ornamental Screening & Trellising
HouseholdBlue Horizon is ideal for covering unsightly fences, walls, and structures with beautiful blue flowers. Its vigorous growth quickly fills vertical space and creates a living privacy screen. [source]
Pollinator Attraction
WildlifeThe abundant, nectar-rich flowers attract bees, butterflies, and hummingbirds, supporting pollinator populations in gardens. Morning glory flowers are particularly attractive to morning-feeding insects. [source]
Seed Collection & Propagation
CraftBlue Horizon produces viable seeds that can be collected and saved for planting next year, making it economical for gardeners who want to propagate new plants annually. [source]
Container & Hanging Basket Growing
HouseholdBlue Horizon works beautifully in large containers and hanging baskets with a small trellis support, bringing morning glory flowers to patios and balconies. [source]
Seasonal Color & Cut Flower Arrangements
HouseholdFresh morning glory flowers can be cut early in the morning for short-lived but stunning floral arrangements, though they typically close by afternoon. [source]
Harvest Tips
Blue Horizon is grown as an ornamental for flowers, not harvested for edibles. Deadhead spent flowers regularly to promote continuous blooming throughout the season. To collect seeds, allow the last flowers to develop into mature seed pods in late summer/early fall. Harvest pods when they turn brown and papery, then dry indoors and store in a cool, dry place for next season's planting.
Fun Facts
- 🌱 Morning glory flowers open in the early morning (hence their name) and typically close by afternoon, a behavior driven by the plant's internal circadian rhythm.
- 🌱 Blue Horizon and other morning glories have been used in traditional medicine in Central and South America; the seeds contain compounds that have been studied for various pharmacological properties.
- 🌱 A single Blue Horizon vine can produce hundreds of flowers over a growing season, with new buds forming continuously from summer until the first hard frost.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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