Moonflower (Ipomoea alba)

Moonflower, Moonvine, Tropical White Morning Glory

Moon flower, scientifically known as Ipomoea alba, is a fast-growing climbing vine that is native to tropical regions of the Americas. Large, fragrant, white or pale pink trumpet-shaped blooms on this lovely plant are well-known for blooming at night and closing during the day. Moon flowers are not only famous for their beauty but also for their sweet and captivating fragrance, which attracts moths, bats, and other night-flying insects. These climbing vines can grow several meters in length, making them ideal for growing on trellises, fences, or walls. 

I. Appearance and Characteristics 

Ipomoea alba, sometimes called the tropical white morning-glory, moonflower or moon vine, is a species of night-blooming morning glory, native to tropical and subtropical regions of North and South America, from Argentina to northern Mexico, Arizona, Florida and the West Indies. Though formerly classified as genus Calonyction, species aculeatum, it is now properly assigned to genus Ipomoea, subgenus Quamoclit, section Calonyction.

Ipomoea alba is a perennial, herbaceous liana growing to a height of 5–30 m (16–98 ft) tall with twining stems. The leaves are entire or three-lobed, 5–15 cm (2.0–5.9 in) long, with a 5–20 cm (2.0–7.9 in) long stem. The flowers are fragrant, white or pink, and large, 8–14 cm (3.1–5.5 in) diameter. The flowers open quickly in the evening and last through the night, remaining open until touched by the morning dew. On overcast days, the blossoms may remain open for longer. The flowers also tend to remain open longer during cool temperatures, which may also cause the segments to snag or tear as they open.

The name moonflower derives from their blooming in the evening and their being round in shape like a full moon.

II. How to Grow and Care

Moonflower vines require fairly simple maintenance with regular watering and feeding, and they rarely suffer from serious pest or disease problems. Because they have a climbing growth habit, it’s ideal to provide them with a trellis or other support structure they can grow around. They also can be allowed to spread naturally as a ground cover or grown in hanging baskets and containers. If possible, plant them near a deck or bedroom window where you can enjoy their sweet fragrance at night. 

Sunlight

Moonflower grows best in full sun, meaning at least six hours of direct sunlight on most days. It can adapt to partially shady conditions, though it might not flower as well.

Temperature and Humidity

These vines thrive in the summer warmth and humidity in zones 3 to 9, and will be perennial in zone 10 to 12. If you live in a cooler climate, wait to plant them outside until the temperature is reliably around 60 to 70 degrees Fahrenheit. Native to tropical climates, these plants prefer a fairly high humidity level but will tolerate dry air if they are kept well-watered.

Watering

Moonflower likes a moderate amount of soil moisture. Water young plants regularly, so their soil stays moist but not soggy. Soil that’s too wet can cause the roots to rot. Water established plants when the top inch of soil feels dry. The vine will tolerate short periods of drought, but a long dry spell can kill it.

Soil

This vine can tolerate a variety of soil types. But it prefers a rich, loamy soil with good drainage and a slightly acidic to neutral soil pH.

Fertilizing

Fertilize every three to four weeks with a half-strength, high-phosphorus fertilizer when the plant is in bloom. Avoid high-nitrogen fertilizer, as it can promote excessive foliage growth at the expense of blooms.

Pruning

As an annual, you can prune this plant back after the flowering season to give space for next year’s plant to grow.

Bear in mind, however, that I. alba puts forth attractive and intriguing seed pods after flowering, and some gardeners decide to keep these plants around a little longer so they can enjoy these seeds.

As an enthusiastic grower, you may find yourself wanting to trim back your moonflower vine throughout its flowering season to keep it looking tidy and organized.

This is fine, just be careful not to prune back too aggressively.

Propagation

Moonflowers are fairly difficult to propagate by rooting vegetative stem cuttings, so it’s rarely attempted. However, the plant self-seeds very freely, so it’s quite easy to obtain new plants by transplanting the volunteers that readily sprout up from seeds dropped in the garden. Here’s how:

  • Look for tiny seedling plants sprouting in the garden. Often, these will appear in spring in the location where the previous year’s mature plants dropped their seeds.
  • Using a small garden trowel, carefully dig up and transplant the volunteer seedling to a new location. Be very careful, as moonflower does not like its roots to be disturbed. If propagating late in the season, you can transplant them into small individual pots to grow indoors over the winter, then move them outdoors in the spring. However, potted indoor seedlings will probably need a small support structure to hold the vines, which will grow rapidly. Peat planting containers are a good choice for this method.

Grow Moonflower From Seed

If you are harvesting seeds from an existing vine, make sure they have fully dried before you collect them from the seed pods left behind after the flowers fade. Start seeds indoors roughly four to six weeks before your area’s projected last frost date. Soak the seeds overnight in warm water or slightly nick them with a file to break their hard coating. 

Then, plant them about 1/4 inch deep in a seed-starting mix. It’s ideal to use small biodegradable peat pots that you can just bury in the garden, as moonflower doesn’t like its roots disturbed with transplanting. Place the seeds in a warm spot that gets bright, indirect light, and keep the soil lightly moist until seedlings appear. Once outdoor temperatures are reliably warm, you can begin acclimating the seedlings to direct sunlight by placing them outdoors for increasingly long stretches each day. After about a week of this hardening-off procedure, the seedlings are ready to be planted outdoors.

Overwintering

In cold-winter zones where you are growing moonflower as an annual, pull the entire plant from the ground when the flowers have faded and the foliage begins to wither and turn brown. Leaving the vines in place may lead to a vast number of volunteer seedlings in the spring. Because these plants self-seed so vigorously, it’s best not to add the dead plants to compost heaps, since many seeds are likely to survive.

In warm-weather zones where moonflowers continue to grow as perennials, winter is a good time to survey the ground and pluck out volunteer plants to prevent uncontrolled spread.

Pests and Diseases

Common Diseases 

Moonflower can fall prey to black rot, a bacterial disease that thrives in humid conditions. It can be remedied by separating thick vines to promote air circulation, and never watering from overhead or at night, which will keep the plant drier.

Common Problems 

Moonflower is an easy-going plant that needs very little care. But it can have a few problems that are easy for any gardener to fix.

Yellow Lesions on the Edges of Leaves

This more than likely means your moonflower has black rot, a bacterial disease that if left untreated will force your plant to drop its leaves. But you can fix this because it comes from over-crowding and too much moisture: Untangle your vines to space them out, and never water in the evening or from above.

Seedlings Die for No Reason

This is called damping-off disease, and it happens to seemingly healthy seedlings without warning. To keep this from happening, do not over-water seedlings, and do not overcrowd them in your garden. Thin your plants out so they get more air circulation; this should help avoid damping off. When starting seeds, using a porous seed-starter mix rather than standard potting soil, and making sure air circulation is good can prevent damping-off fungus.

III. Uses and Benefits 

  • Ornamental purposes 

Moon flowers are grown for their large, white, trumpet-shaped flowers that open at night and close in the morning. They are a well-liked option for landscapers and gardeners who wish to enhance the beauty and aroma of their gardens and yards.

  • Cut flowers

Moon flowers are often used as cut flowers in arrangements and bouquets due to their large size and delicate beauty. Their fragrant blooms can add a touch of natural fragrance to any room.

  • Medicinal uses

Moon flowers have been used for medicinal purposes in some traditional cultures. Their seeds are believed to have sedative and antispasmodic properties, and have been used to treat a variety of ailments, including anxiety and insomnia.

  • Culinary uses

Moon flower leaves and stems are edible, and have been used as a food source in some cultures. The leaves are sometimes used to wrap food, and the stems can be sliced and used as a vegetable.

  • Landscaping

Moon flowers can be grown as climbing plants and used to cover walls, fences, or arbours. They are also sometimes grown in containers, making them a versatile choice for many different types of landscaping projects.

Moonflower (Ipomoea alba) Details

Common name Moonflower, Moonvine, Tropical White Morning Glory
Botanical name Ipomoea alba
Plant type Vine
Hardiness zone 10a, 10b, 11a, 11b, 12a, 12b
Growth rate Fast
Height 10 ft. 0 in. - 30 ft. 0 in.
Width 10 ft. 0 in. - 30 ft. 0 in.
Sunlight Full sun (6 or more hours of direct sunlight a day)
Soil condition Clay
Flower color White
Leaf color Green