Heavenly Blue morning glory flowers in sky-blue with white throats climbing a trellis

How to Grow Heavenly Blue Morning Glory From Seed

By Maxim Kaufman — Founder & CEO, Organo Republic

Updated July 2026

Heavenly Blue is the morning glory everyone pictures: an heirloom climber covered in large, pure sky-blue trumpets with bright white throats. Each flower stretches 4 to 5 inches across, opening in the morning and giving way to fresh blooms the next day. The vines twine 6 to 10 feet up an arch, arbor, or trellis and flower generously from mid summer until frost. Here is a quick-start guide to growing this classic variety from seed.

This is the quick guide to Heavenly Blue. For the full step-by-step on scarifying and soaking seeds, sowing, training the vines, and troubleshooting morning glory, see our complete guide to growing morning glory from seed.

Quick start

Nick each seed and soak it in warm water for 12 to 24 hours, then direct sow half an inch deep and about 6 inches apart at the base of a trellis, arbor, or fence once frost has passed and the soil is warm. Give Heavenly Blue full sun and lean, well-drained soil, and go easy on fertilizer to encourage flowers over foliage. Seedlings emerge in 5 to 14 days, and the vines climb 6 to 10 feet, opening their first sky-blue trumpets in mid to late summer. Because this variety can bloom a little later, sow early after frost so it has the whole warm season to flower until fall.

Best tip

Sow Heavenly Blue early and in full sun so it has time to bloom. This classic variety can flower a bit later than others, so getting it into warm soil right after your last frost, or starting it indoors in peat pots in cooler climates, gives it the long, hot season it needs to cover itself in those iconic 4 to 5 inch blue trumpets before fall.

At a glance

Botanical nameIpomoea tricolor 'Heavenly Blue'

Plant typeAnnual flowering vine

USDA zones2 to 11 (grown as an annual)

SunFull sun

Days to maturity80 to 100 days to bloom

Height6 to 10 ft climbing vine

Spacing6 in apart

WaterModerate; water during dry spells

Uses

Heavenly Blue is the showpiece morning glory, prized for its large, pure sky-blue flowers with white throats. Train it up an arch, arbor, entryway, or trellis where its dramatic blooms can be admired each morning. The flowers are a favorite of hummingbirds and bees, making it a standout in pollinator and cottage gardens. Grow it as an ornamental only, as the seeds are toxic if eaten.

Frequently asked questions

What makes Heavenly Blue morning glory special?

Heavenly Blue is the iconic heirloom morning glory, famous for its large, pure sky-blue flowers with soft white and pale-yellow throats. The blooms measure a generous 4 to 5 inches across and cover the vine daily through summer. It is the classic variety most gardeners picture when they think of morning glory.

How big are Heavenly Blue flowers?

The trumpet-shaped flowers are large, about 4 to 5 inches wide, in a clear sky-blue with a bright white throat. Their size and true-blue color make them stand out on any trellis or arbor. Each bloom opens in the morning and fades by afternoon, replaced by fresh flowers the next day.

Does Heavenly Blue bloom later than other morning glories?

Heavenly Blue can be a slightly later bloomer than some varieties, often opening its first flowers in mid to late summer and then flowering heavily right up to frost. Sowing early after your last frost and giving it full sun helps it start blooming as soon as possible. Once it begins, it flowers generously until cold weather arrives.

How tall does Heavenly Blue morning glory grow?

Heavenly Blue is a strong climber that reaches 6 to 10 feet or more in a single season on a trellis, fence, or arbor. Give it full sun and a sturdy support and it will twine upward quickly through summer. Its height and dramatic blue flowers make it a favorite for arches and entryways.

Ready to grow your own Heavenly Blue morning glory? Start with our heirloom, non-GMO 21 Annual Wildflower Mix for an easy, colorful summer, and explore more climbers in our wildflower seeds collection.

21 Annual Wildflower Seeds MixEasiest way to startOur 21 Annual Wildflower Mix packs morning glory alongside a summer of fast, easy blooms for beds, borders, and pollinators.$24.99$22.99

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Want more blooms around your Heavenly Blue vines? These value packs pair it with other easy wildflowers:

16 Perennial Wildflower Seeds MixComes back every year16 Perennial Wildflower Mix fills the beds below your morning glory trellis with blooms that return season after season.$14.99$12.99

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23 Birds & Butterflies Wildflower Seeds MixPollinator magnet23 Birds & Butterflies Mix draws the hummingbirds and bees that already love morning glory into one buzzing, fluttering garden.$14.99$12.99

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By Maxim Kaufman — Founder & CEO, Organo Republic

Maxim founded Organo Republic in 2017 and personally selects, tests, and grows the heirloom, non-GMO varieties the company offers. Under his leadership, Organo Republic was named Agri Business Review’s Top Non-GMO Seed Variety Solution 2026.