How to Grow and Care For Moonflower

Moonflower (Ipomoea alba), sometimes called night-blooming morning glory, is a tender perennial vine that can add incredible beauty and powerful fragrance to a night garden. It features large, heart-shaped, dark green leaves, robust, slightly prickly stems, and white trumpet-shaped flowers blooming at night from midsummer until fall.

Moonflower grows best in moist, well-draining conditions, with six hours of full sunlight, slightly acidic to neutral soil, and temperatures above 60°F. Plants in the Ipomoea genus, like moonflower, are toxic to humans, dogs, cats, and horses.

Fast Fact

Moonflower (Ipomoea alba) is unrelated to Datura inoxia, also commonly called moonflower, which also has white trumpeting flowers and is toxic.

How to Plant Moonflower

Moonflower is best planted in the spring in a full-sun location after the danger of frost has passed. As this plant blooms and releases its sweet perfume at night, consider planting near an open window, deck, or patio to enjoy its scent and pretty flowers. It can also grow in hanging containers or as a ground cover. This vining plant likes to climb, so provide a trellis or support structure.

Moonflower Care

Moonflowers are an invasive species in Hawaii; they also have weed-like growing tendencies in the subtropical regions of Florida and the southern tip of Texas. Here are the main care requirements for growing a moonflower:

• Provide moist but well-draining soil with a slightly acidic to neutral pH.
• Needs at least six hours of full sun.
• Prefers a trellis or climbing structure for its vine-like growing habit.
• Requires warm temperatures to thrive, specifically above 60°F.
• Give fertilizer every three to four weeks.

Light

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.

Soil

This vine can tolerate a variety of soil types, but it prefers rich, loamy soil with good drainage and a slightly acidic to neutral soil pH (6.0—7.5).

Water

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.

Temperature and Humidity

These vines thrive in the summer warmth and humidity in zones 3 to 8 and will be perennial in zones 9 to 12. If you live in a cooler climate, wait to plant them outside until the temperature is around 60 to 70°F. Native to tropical climates, these plants prefer a relatively high humidity level but will tolerate dry air if they are kept well-watered. In cooler regions, this plant dies annually during cold weather.

Fertilizer

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.

Types of Moonflower

• Datura inoxia is unrelated to Ipomoea alba but is also called moonflower. It also goes by the name jimsonweed or pricklyburr. It looks similar with its white trumpeting flowers and is also toxic. Datura differences: It blooms in the daytime, has an unpleasant smell, has arrow-shaped leaves, and its flowers have a deeper trumpet shape with tiny spurs on the outer edge of the bloom. It grows more like a bush. It is in the nightshade family and closely related to brugmansia.
• Ipomoea alba is a fast-growing vine and can reach around 10 to 20 feet long in just one season under optimal conditions. Similar moonflower species include Ipomoea leptophylla, bush moonflower or bush morning glory, and Ipomoea violacea, or beach or sea moonflower.
  

Pruning

When grown year-round outdoors as a perennial, the vines can be pruned back and shaped as needed in the fall. Thin the stems to improve airflow around the plant and open it to sunlight.

Pruning Tip

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Propagating Moonflower

Moonflowers are relatively tricky to propagate by rooting vegetative stem cuttings, so this method is 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.

Carefully dig up tiny plants sprouting in the garden using a garden trowel. Often, these will appear in spring in the location where the previous year's mature plants dropped their seeds. They don't like uprooting, so be gentle with the root ball. If transplanting at the end of the growing season, pot them into peat planters and provide a support structure for the vines to climb.

How to Grow Moonflower From Seed

If you are harvesting seeds from an existing vine after the flowers fade, remove the seed pods when they look like small, dry husks. The seeds can be planted immediately or stored in a cool, dry place until the next growing season.

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.

• Plant the seed about 1/4 inch deep in a seed-starting mix. Small biodegradable peat pots you can bury in the garden are ideal. Moonflowers don’t like transplanting, which disturbs their roots.
• Place the pot in a warm spot with bright, indirect light, and keep the soil lightly moist until seedlings appear.
• Acclimate the seedlings to direct sunlight by placing them outdoors for increasingly long stretches each day once outdoor temperatures are reliably warm.
• Transplant the seedlings after a week of gradual hardening or acclimation.

Potting and Repotting Moonflower

Plant them the same way you would plant seeds in the ground, but use an ordinary potting mix rather than garden soil.

These plants do not like replanting, so plant it into a permanent pot. If growing them upright rather than as hanging baskets, give the plants something to climb, such as a trellis or stake.

Overwintering

When growing moonflower as an annual, most gardeners prefer to start new plants the following year rather than trying to overwinter their plants; the vines can be challenging to maintain indoors.

In cold-winter zones, 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 many volunteer seedlings in the spring. Because these plants self-seed so vigorously, do not 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 remove volunteer plants to prevent uncontrolled spread.

Common Plant Diseases

Moonflower rarely suffers from severe pest or disease problems. However, it can fall prey to black rot, a bacterial disease that thrives in humid conditions. This can be remedied by separating thick vines to promote air circulation and never watering from overhead or at night so the plant leaves remain dry.

How to Get Moonflower to Bloom

On cloudy days, the blooms unfurl from cone-shaped buds as the sun goes down. They stay open all night, exuding their sweet fragrance into the air before closing up in the morning and fading away.

Bloom Months

Ipomoea alba typically blooms in summer and fall, beginning in July and lasting until the first frost. These plants only rebloom perennially in warm tropical zones.

What Do Moonflower Blooms Look and Smell Like?

When the beautiful and mysterious moonflower's creamy white blooms open at night, they provide a light, sweet fragrance. Trumpet-shaped moonflowers are typically an iridescent white and grow around 6 inches long and 3 to 6 inches wide.

How to Encourage More Blooms

Deadheading or removing spent blooms can promote further blooming on the vines. If you don’t want the vines to reseed in your garden, remove the spent flowers before they can drop seeds.

Moonflowers generally bloom reliably if they get enough sun and are watered regularly. Adding fertilizer to your watering routine—moonflower likes a high-phosphorous variety—will help your plant produce more flowers.

Common Problems With Moonflower

Moonflower is an easy-going plant that requires simple maintenance, such as regular watering and feeding. However, it can have a few problems that are simple for any gardener to fix.

Yellow Lesions on the Edges of Leaves

Black rot is a bacterial disease that, if left untreated, will force your plant to drop its leaves. But you can fix this by avoiding overcrowding 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

When healthy seedlings die unexpectedly, it could be a damping-off disease. To prevent damping-off, do not overwater seedlings or overcrowd them in your garden. Thin your plants out to 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 ensuring good air circulation can prevent damping off fungus.

From: thespruce