Common Morning Glory (Ipomoea purpurea)

Common morning glory natives in Mexico and Central America and is commonly planted as an ornamental plant prized for its colorful trumpet-shaped flowers. It is naturalized in temperate and subtropical areas globally and in many places, always grown weedy and is considered to be invasive in many parts of the world.

I. Appearance and Characteristics 

Ipomoea purpurea, the common morning-glory, tall morning-glory, or purple morning glory, is a species in the genus Ipomoea.

Like all morning glories, the plant entwines itself around structures, growing to a height of 2–3 m (6 ft 7 in – 9 ft 10 in) tall. The leaves are heart-shaped and the stems are covered with brown hairs. The flowers are trumpet-shaped, predominantly blue to purple or white, and 3–6 cm (1.2–2.4 in) in diameter.

The plant is predisposed to moist and rich soil, but can be found growing in a wide array of soil types. It is naturalized throughout warm temperate and subtropical regions of the world. Although it is often considered a noxious weed, I. purpurea is also grown for its attractive purple and white flowers, and has many cultivars. Common cultivars include I. purpurea ‘Crimson Rambler’ (red-violet blossoms with white throats), ‘Grandpa Ott’s’, ‘Kniola’s Black Knight’, ‘Star of Yelta’ (blossoms in varying shades of deep purple with white or pale pink throats), and ‘Milky Way’ (white corolla with mauve accents).

II. 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

III. How to Grow and Care

Sunlight

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.

Temperature

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.

Watering

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.

Soil

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.

Fertilizing

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.

How to Grow From Seed

You can start seeds 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.

Pruning

Morning glory is a fast-growing plant that can quickly become out of control. To keep it under control, prune regularly, removing any dead or damaged leaves, stems, or flowers.

Trellising

Morning glory plants are climbers and require support to grow. Install a trellis or provide a support system for the plant to climb.

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.

IV. Uses and Benefits 

Common morning glory is a popular ornamental garden climber with alluring flowers and heart-shaped foliage. The flowers open early, greeting the morning and closing in the afternoon, bringing charm to the garden. Traditionally, it is grown in cottage gardens and Mediterranean gardens, as well as non-traditional gardens such as hanging baskets and containers. It makes an attractive cover on trellises, arbors, fences, or nearby structures.