The common morning glory is often the first flowering vine that gardeners become familiar with. These fast-growing annual vines are in the same botanical family as sweet potatoes although they don't produce edible tubers, in fact, all morning glory species are toxic to people. and toxic to pets.
The brightly colored trumpet-shaped flowers of the common morning glory have a slight fragrance and are popular with butterflies and hummingbirds. The buds are twirled up tightly and unfold when the sun hits them in the morning, giving them their unique name.
Native to Mexico and Central America, common morning glory vines grow by clinging to nearby supports with tendrils, rapidly growing up to 12 feet or more during the season. They can be planted from seed about one month before the last spring frost, and self-sow effusively, making it very likely they'll come back the following year. Though some gardeners find them too aggressive, unwanted seedlings can usually be pulled out easily.
|Common Name||Morning glory, common morning glory|
|Botanical Name||Ipomoea purpurea|
|Mature Size||6–10 ft. tall, 3–6 ft. wide|
|Soil Type||Moist, well-drained|
|Soil pH||Neutral, acidic|
|Bloom Time||Summer, fall|
|Flower Color||Purple, pink, blue, white|
|Hardiness Zones||2–11 (USDA)|
|Native Area||North America|
|Toxicity||Toxic to people, toxic to pets|
Morning Glory Care
The common morning glory is a favorite of gardeners everywhere for good reason. The eye-catching vines are very low maintenance—they can be easily started from seed in early spring, and you don't need to prune or deadhead them as they grow. Have a trellis or other support in place wherever you plant your seeds and the vines will soon find the support and train themselves to grow on it.
With regular watering, morning glories can start blooming by mid-summer, but many times they are slow to begin setting flowers, earning them the nickname "back to school vine." If you want to try and speed up the flowering time of morning glories you seed yourself, you can try sowing the seeds even earlier in the spring by scattering them on the frozen ground and even on snow.
Planting your morning glory in a spot that gets full sun is especially important. The flowers will only open when they are in direct sunlight, so daily exposure to full sun (at least 6 to 8 hours a day) will give you the longest amount of bloom time. If they are in a spot that doesn't get sun until the afternoon, don't expect "morning" glories.
Morning glories do best in soil that is moist but well-draining. A neutral soil pH of 6.0 to 6.8 is best, but morning glories will grow just about anywhere. However, they do bloom better in soil that is not too rich in organic matter. You can always amend the soil later if the vines look like they are struggling.
Provide your morning glories with regular water, about one inch per week, and mulch around the roots to retain moisture. The biggest moisture needs come during the plant's growing period. Once established (and in the winter, if your zone is warm enough to grow the plant as an annual), you can slow your watering cadence.
Temperature and Humidity
Morning glories easily tolerate both cold and warm temperatures; they are hardy and can even make it through the first frost and continue to bloom. They are grown as an annual in areas where the temperature drops below 45 degrees Fahrenheit and can be perennials in tropical and subtropical climates. They have no special humidity needs.
Feed your morning glories with a low-nitrogen fertilizer every four to five weeks throughout their growing period. If you notice a lack of blooms, you can try a fertilizer blend that is high in phosphorous.
Morning Glory Species and Varieties
In addition to cultivars of the common morning glory, there are other Ipomea species with similar appeal:
- I. purpurea 'Star of Yelta': Deep purple blooms with dark red stars and small white throats
- I. purpurea 'Kniola's Black': Another purple-flowered cultivar but with blooms even darker than those of 'Star of Yelta'
- I. tricolor 'Heavenly Blue': A popular cultivar with large azure flowers and heart-shaped leaves
- I. alba: Also called moonflower or belle de nuit; a night-blooming species with 6-inch-wide white flowers
- Ipomoea x multifida: Known as the cardinal climber; a hybrid with relatively small but deep red flowers resembling morning glory blooms
How to Grow Morning Glory From Seed
You can start seed indoors about four to six weeks before your last frost date, but it's not necessary—morning glory does very well when direct-sown as well. If you prefer to plant your seeds straight into the ground, wait until the soil is able to be worked and has warmed to at least 64 degrees Fahrenheit.
Morning glory seeds have a very hard seed coat and germination will be faster with scarification. You can do this by rubbing the seeds between two pieces of coarse sandpaper for a few seconds and then soaking them overnight. You will notice they are a lot plumper in the morning and look ready to sprout.
Sow the seeds about 1/4 inch deep, spaced a few inches apart. If you are planting a row of morning glories, six-inch spacing will be fine. If you are planting a trellis, you don't need to be too particular about spacing. Water the seeds well and keep the soil moist until they sprout.
Common Pests and Diseases
Morning glory vines are seldom bothered by insects or diseases, although they can contract several fungal problems like leaf spot, stem rot, thread blight, and white blister if they experience a lot of wet weather.
A bigger problem is wildlife who loves to munch on morning glory leaves without ill effects. Deer, rabbits, and groundhogs can do a lot of damage to the lower vines, especially while plants are young. Prevent critters from getting to your morning glories by fencing around the lower three to five feet of the vines. The vines will eventually grow through the fencing and disguise it all together. At that point, if animals do a little browsing, it shouldn't kill the whole plant.
Which parts of the morning glory are toxic?
It's the seeds that contain the toxic alkaloids but as a precaution, you should keep children and pets away from the entire plant, or abstain from growing it at all.
Is morning glory an invasive plant?
It can become invasive because it reseeds itself freely and its vigorous growth can choke out other plants.
Is morning glory a creeper or a climber?
It depends on the species. The common morning glory is a climber that needs a trellis or some other sort of support whereas the coast morning glory (Ipomea cairica) is a creeper.
Safe and Poisonous Garden Plants. University of California.