As the name implies, morning glory flowers, which are funnel-shaped, open in the morning, allowing them to be pollinated by Hummingbirds, butterflies, bees, and other daytime insects and birds as well as Hawkmoth at dusk for longer blooming variants. The flower typically lasts for a single morning and dies in the afternoon. New flowers bloom each day. The flowers usually start to fade a couple of hours before the petals start showing visible curling. They prefer full sun throughout the day and mesic soils. In cultivation, most are treated as perennial plants in tropical areas and as annual plants in colder climates, but some species tolerate winter cold. Some moonflowers, which flower at night, are also in the morning glory family.
You may train shoots that have not yet chosen something around which to twine. If any shoot grows long enough without having found a place to twine, gently guide it to the nearest suitable twining spot. Twigs are very useful for getting a shoot to move away from the mother plant and become its own vine. Do not untwine a shoot that has already wound around something -- it will simply stop growing.
Morning glories are self propagating. Each plant will give you two to ten flowers daily, and each flower will produce a pod of six seeds. Many people let morning glories become bush-like, letting the seeds fall to the ground and grow. Others prefer to preserve the vine-like aspect of this delicate but hardy plant. This requires that you cull the seeds when they are about to drop. Simply keep an eye on the seed pods left behind by the flowers. The plant holds on to the pods with tiny leaves. When the pod is about to drop, the tiny leaves begin to curl away from the pod. The pod itself turns from pale green to brownish, and the covering of the pod becomes papery. If you just want to keep the vines in check, you may clip their pods at any time. If you have cold winters and would like to save the seeds to replant in the spring, or want to grow them in an additional spot, let the pods become almost papery, then clip the pods and save the seeds.
If you'd like to keep your vines from becoming bushes, use selective pruning. Clip pods that are finished with their job. Clip close to the last branching point. Clip unhealthy leaves in the same way. If part of the vine stops growing, you may clip it back to the last budding point; this will encourage shoots from other points in the vine. If you don't clip the pods, many vines will grow very close together so that they look like bushes. This is a pretty way to completely cover a fence.
To plant morning glories, separate the pods into seeds. Put the seeds in tepid water for about a day. Then push them into the soil with your finger, no more than one inch deep, being sure to cover the little hole with soil. They like fertilized and well draining soil, but can flourish in almost anything. In you have hard freezes, the perennial but tropical morning glory will behave like an annual, so save some seeds for spring. If you plant late in the season you will get fewer flowers, but the heart-shaped leaves are lovely. In winter areas, plant just after the last frost in the spring for fast-growing, multi-flower producing vines.
Water the seeded area daily, and be sure the seedlings get plenty of water. The water should be poured at ground level, very close to the root, so as not to disturb the tender new stems. Once you have vines, wilting leaves will let you know that they need water; water the roots, and the leaves will spruce up in an hour or two.
Too much water, especially without enough sun, will lead to mold spots on the leaves -- white or gray spots, a few millimeters in diameter, that eventually become holes in the leaves. You may clip off these leaves, but I leave mine on as long as possible because they are still soaking up the little bit of sun that they get in my very limited growing area. The mold is unsightly, but does not spread to neighboring vines.
Morning glory is also called asagao (in Japanese, a compound of 朝 asa "morning" and 顔 kao "face"). A rare brownish-coloured variant known as Danjuro is very popular. It was first known in China for its medicinal uses, due to the laxative properties of its seeds. It was introduced to the Japanese in the 9th century, and they were first to cultivate it as an ornament. During the Edo Period, it became a very popular ornamental flower. Aztec priests in Mexico were also known to use the plant's hallucinogenic properties. (see Rivea corymbosa).
Ancient Mesoamerican civilizations used the morning glory species Ipomoea alba to convert the latex from the Castilla elastica tree and also the guayule plant to produce bouncing rubber balls. The sulfur in the morning glory's juice served to vulcanize the rubber, a process pre-dating Charles Goodyear's discovery by at least 3,000 years.
Because of their fast growth, twining habit, attractive flowers, and tolerance for poor, dry soils, some morning glories are excellent vines for creating summer shade on building walls when trellised, thus keeping the building cooler and reducing heating and cooling costs.
Popular varieties in contemporary western cultivation include the Morning Glory "Sunspots" "Heavenly Blue", the moonflower, the cypress vine, and the cardinal climber. The cypress vine is a hybrid, with the cardinal climber as one parent.
In some places such as Australian bushland morning glories develop thick roots and tend to grow in dense thickets. They can quickly spread by way of long creeping stems. By crowding out, blanketing and smothering other plants, morning glory has turned into a serious invasive weed problem.