Morning Glory (Annual)

Morning glories are best direct-sown outdoors after the last frost when soil temperatures have warmed to at least 65 degrees Fahrenheit. Nick the hard seed coat with a file or soak seeds overnight in warm water to speed germination. Plant seeds one-half inch deep and six inches apart at the base of a trellis, fence, or other support structure. Seeds germinate in five to ten days in warm conditions.

Provide a sturdy support immediately, as vines grow rapidly and can reach ten to fifteen feet in a single season. Morning glories climb by twining counterclockwise, so vertical strings, wires, or lattice work best. Full sun is essential for abundant blooming, and lean soil is actually preferable, as fertile soil promotes excessive foliage with fewer flowers.

Water moderately during establishment, then reduce to minimal irrigation. Morning glories are drought-tolerant once established and bloom most heavily under slight stress. Avoid fertilizing, especially with nitrogen, as this produces vigorous leafy growth but delays and reduces flowering. Remove seed pods to control self-sowing, which can be aggressive in warm climates. The seeds are toxic if ingested.

Ipomoea purpurea, the common annual morning glory, is native to tropical and subtropical regions of Central America and Mexico, where it has been cultivated for thousands of years. Archaeological evidence suggests that indigenous peoples of Mesoamerica used morning glory species both as ornamental plants and for ceremonial purposes. The Aztecs referred to certain morning glory species as 'tlitlitzin' and valued them within their cultural and medicinal traditions. Spanish explorers encountered the plant during the sixteenth century and brought seeds back to Europe, where morning glories quickly gained popularity as ornamental garden climbers. By the early seventeenth century, the plant had spread across European gardens and eventually reached Asia through maritime trade routes. In Japan, morning glories arrived around the ninth century and became the subject of intense horticultural selection during the Edo period, when Japanese growers developed extraordinary mutant forms with frilled, starred, and multi-colored petals. Annual morning glory exhibitions became popular social events in Tokyo, a tradition that continues to this day at temples and botanical gardens. The plant naturalized readily in warm climates worldwide and is now found on every inhabited continent. In the United States, morning glories became a staple of cottage gardens and rural fencerows by the nineteenth century. Thomas Jefferson grew morning glories at Monticello and noted their rapid growth in his garden journals. Today, Ipomoea purpurea is appreciated globally as an easy-to-grow, vigorous annual vine that provides quick vertical coverage, abundant colorful blooms, and reliable self-seeding behavior in temperate and tropical gardens alike.

Morning glories actually prefer poor to average, well-drained soil with a pH of 6.0 to 6.8. Rich, fertile soil produces vigorous leafy vines with few flowers. Do not amend the soil with compost or fertilizer before planting. Only feed if plants appear stunted or yellowed, using a low-nitrogen phosphorus-rich fertilizer to promote blooms. Container-grown morning glories may need occasional light feeding. Sandy or gravelly soil is ideal for maximum flower production.

Morning glory flowers are short-lived, each bloom lasting only one day, so they are not ideal for cutting. Enjoy them on the vine instead. For seed saving, allow seed pods to dry completely on the vine until they turn brown and papery, then crack open and collect the triangular black seeds. Seeds are easy to save and store. Morning glory vines can be cut and woven into decorative wreaths in autumn after frost kills the foliage. Handle seeds with care, as they are toxic if ingested.

Morning glory flowers cannot be preserved as cut flowers due to their one-day bloom cycle. Individual blooms can be pressed between heavy books for crafting. Seeds are the primary thing to save, and they store excellently for three to five years in paper envelopes in a cool, dry location. Label saved seeds with variety name and harvest date. Dried vines can be fashioned into rustic wreaths. Do not eat or allow children to handle the seeds, as they contain toxic compounds.