Ornamental · Convolvulaceae
Morning Glory
Ipomoea purpurea
Sow a few scarified seeds at the base of a trellis and morning glory will cover it in trumpets by late summer.
Full sun
Every 5–10 days
50–95°F · 10–35°C
65–110 days
Overview
Morning glory is a fast twining annual vine that opens fresh trumpet flowers each morning and lets them fade by afternoon. Native to warmer parts of the Americas, it climbs anything within reach, from a mailbox post to a chain-link fence, and a single season's growth can clear 6 to 10 feet. The classic is sky-blue, but the flowers come in purple, wine-red, white, and striped forms too.
It asks for very little. Full sun, lean soil, and a structure to climb are about the whole list, and rich ground actually works against it by trading flowers for foliage. The catch is that it sows itself freely, so the same vigor that fills a trellis fast can leave you pulling volunteers for years if you let the pods shatter.
Two things are worth knowing before you plant. The seeds carry toxic alkaloids that make them dangerous to pets, livestock, and people who mistake them for something edible. And while the ornamental annual is well behaved compared with its perennial cousin field bindweed, some Ipomoea species are listed as noxious weeds, so check before you sow in a new region.
Care
The short version: full sun and lean, well-drained soil, water when the top half dries, give it a trellis to climb, and skip the fertilizer so you get flowers instead of a wall of leaves.
Light
Give morning glory full sun, meaning 6 or more hours of direct light a day. It will climb in part shade, but you'll see far fewer flowers, since the blooms depend on sun and heat.
Water
Let the top half of the soil dry between waterings, then water deeply, which works out to roughly every 5 to 10 days. Once established the vine is fairly drought tolerant, and soggy soil does it more harm than a dry spell.
Soil
Lean ground suits it best. Plant in average to poor, well-drained sandy soil anywhere from a pH of 5.5 to 8.0, and resist the urge to enrich it, since rich soil grows leaves at the cost of flowers.
Temperature
Morning glory is a warm-weather plant, happy from about 50°F to 95°F (10°C to 35°C). It won't tolerate frost, so wait until the cold has fully passed before setting plants out.
Humidity
Ordinary outdoor humidity is all it needs, so there's no target to hit. Hot, dry air is more likely to invite spider mites than to bother the vine itself.
Feeding
This is one plant you can leave unfed. Skip the fertilizer, or use only a low-nitrogen feed if anything, because rich soil and extra nitrogen grow lush vines with hardly a flower.
Pruning
Pinch the young tips to push the vine into branching, and cut it back whenever it outgrows its space. Clip off the spent seed pods to keep it from sowing itself across the garden.
Repotting
Morning glory is grown fresh from seed each year as an annual, so there's no repotting to think about. Start it where you want it to climb and let it run for the season.
Size & spacing
Expect a vine of 6 to 10 feet (1.8 to 3 m) in a single season, spreading 3 to 6 feet (90 to 180 cm) wide. Give it a sturdy trellis, string, or fence and room for the twining stems to wander.
When to plant
Morning glory needs warmth and dies at the first hard frost, so there's no rushing it. Start seeds indoors in early spring or sow them straight into warm ground once the cold has passed, and the vine blooms from midsummer right up to fall frost.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: 6-8 weeks before last spring frost; scarify and soak seed 12-24 hours
- Plant: 1-2 weeks after last spring frost when soil is warm; or direct sow after frost
- Harvest: midsummer to fall frost (about June to October)
Hardiness
USDA hardiness zones: 2–11
Temperature: down to -46°C
Troubleshooting
Most morning glory complaints come down to too few flowers, too many seedlings, or a run-in with mites and aphids. Match what you see below and step in early, especially with self-seeding, which is far easier to head off than to undo.
Plenty of leafy vine but hardly a flower
This is too much of a good thing, usually rich soil or a nitrogen feed pushing leaf growth at the expense of buds. Morning glory blooms best when it's a little hungry and sitting in full sun, so stop feeding and make sure it gets 6 or more hours of direct light. If the plant is still young, give it time, since flowering doesn't really start until midsummer.
Fix:
- Stop fertilizing and avoid nitrogen-rich amendments
- Move or grow in full sun (6+ hours)
- Be patient; blooms typically start midsummer and continue to frost
New seedlings popping up everywhere next spring
Morning glory is a prolific self-seeder, and pods left to shatter scatter seed across the bed. You'll spot the volunteers by their heart-shaped leaves crowding last year's planting. Pull them young while they come out easily, and clip the spent pods before they ripen if you want to keep the vine in bounds.
Fix:
- Pull unwanted seedlings while young
- Remove and discard spent seed pods before they shatter
- Deadhead flowers before seed set in areas where weediness is a concern
Stippled, yellowing leaves with fine webbing or insects
Fine webbing and a dusty, speckled look point to spider mites, which thrive in hot, dry spells. Aphids cluster on the soft new growth, and leaf miners trace pale tunnels through the foliage. Blast the plant with a strong jet of water to knock the worst of them off, follow up with insecticidal soap if they hang on, and keep the vine watered so mites have less of an opening.
Fix:
- Spray plants with a strong jet of water to dislodge mites and aphids
- Treat persistent infestations with insecticidal soap or horticultural oil
- Remove heavily mined or chewed leaves
Toxicity
This is not a plant to grow where curious pets or small children roam unsupervised. The seeds are the real hazard, packed with LSA alkaloids that cause stomach upset and hallucinations if swallowed, and the foliage is a milder caution. Keep seed packets and dropped pods well out of reach.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Moderate
A nibble of leaf tends to bring on drooling and vomiting. The real danger is the seeds, which carry LSA alkaloids that can leave a cat agitated, wobbly, and disoriented.
Dogs Moderate
Dogs that chew the foliage usually get an upset stomach and some vomiting. Eat a mouthful of seeds and the alkaloids take hold, with tremors, restlessness, and a drunk, stumbling look following soon after.
Horses Moderate
Grazing the vine can churn a horse's gut and leave it dull. A larger dose of seed pushes things further into neurologic territory, with twitching and a dazed, hallucinatory state.
Rabbits Moderate
The same seed alkaloids that trouble dogs and cats hit rabbits too, so keep this vine well out of reach. Watch for a rabbit going off its food, sitting hunched, or acting unsteady.
Livestock Moderate
Cattle, sheep, and goats rarely seek it out, but a mouthful of seed-laden vine can bring colic and odd, agitated behavior. Pull stray morning glory from pasture fencing where stock can reach it.
Birds Caution
Treat morning glory as off-limits for pet birds. The seeds hold the strongest dose of alkaloids, so keep packets and dropped pods away from cages and aviaries.
People Caution
No part of this plant is meant to be eaten. The seeds are genuinely hazardous, holding LSA alkaloids that bring nausea and hallucinations, so keep them away from children and never treat them as food.
Keep seed packets and dropped seeds away from pets and children; the seeds are sometimes abused for their hallucinogenic alkaloids.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Morning glory comes in a wide range of colors and a few close relatives worth knowing. These are the ones you'll meet most often.
Heavenly Blue (Ipomoea tricolor)
The one most people picture, with clear sky-blue trumpets opening from a pale white and yellow throat.
Grandpa Ott's
A deep-purple heirloom marked by a reddish-magenta star burning up the center of each bloom.
Scarlett O'Hara
Carries rich wine-red to scarlet flowers that stand out against the usual blues and purples.
Flying Saucers / Pearly Gates (Ipomoea tricolor)
A matched pair where Flying Saucers swirls blue and white together while Pearly Gates blooms pure white.
Moonflower (Ipomoea alba)
A night-blooming cousin whose large white flowers unfurl in the evening and carry a sweet scent.
Cardinal climber / Cypress vine (Ipomoea × multifida / Ipomoea quamoclit)
Related vines grown for their fine, fern-cut foliage and small red star-shaped flowers.
How to propagate
Morning glory is grown from seed, and the only trick worth learning is how to get that hard seed coat to open.
SeedEasy
Start indoors 6-8 weeks before last frost or direct sow after frost when soil is warm · Germinates in about 1-2 weeks after scarifying/soaking; rapid growth once established
Morning glory grows from seed and nothing else. The seed coat is hard, so nick it with a file or sandpaper and soak the seeds for 12 to 24 hours before planting. Start them indoors 6 to 8 weeks before your last frost, or sow straight into warm ground once frost has passed, and they sprout within 1 to 2 weeks before taking off fast. Give the twining vine a trellis, string, or fence to climb the moment it's up.
Myths
Morning glory and field bindweed are the same weedy plant.
They look alike but they are two different species. Ornamental morning glory is a warm-season annual in the genus Ipomoea, with showy 2-inch flowers and heart-shaped leaves that die off at frost. Field bindweed is Convolvulus arvensis, a deep-rooted perennial noxious weed with smaller 1 to 1.5-inch white-to-pink flowers and narrow arrowhead leaves, and it's the one that earns the bad reputation.