Moonflower is the common name of species of Ipomoea that bloom at night and have big white or purple blooms with long corolla tubes that expand abruptly into a large, flat limb or face from which the stamens and style protrude. Tender perennials, these kinds were previously separated as the genus Calonyction. Some are commonly cultivated as annuals. The most popular, I.alba (syns. I. bona-nox, Calonyction aculeatum) is a milky-juiced, nearly or quite hairless vine 10 to 20 feet tall or taller. Native of the tropics,, it occurs spontaneously in southern Florida. Its heart-shaped, angular or three-lobed, long stalked, pointed leaves are 3 to 8 inches across. The fragrant, white or slightly greenish-white flowers, one to seven on stalks 2 to 6 inches long, pop open in the evening and usually close by morning, but sometimes remain open until noon. They have sepals about 1/2 inch long, corolla tubes 3 to 6 inches long, and across the face of the bloom measure 3 to 6 inches.
They adapt to a wide variety of sites and soils. In general they prefer well-drained, loamy soils of at least moderate fertility and with ample moisture, but some, such as the hardy bush morning glory (I. leptophylla) and the tropical I. pes-caprae, flourish in dry soils and dry climates. Practically all are sun lovers. Even those that will grow in some shade usually do not bloom well under such conditions. Most of the perennial species are not hardy in the north, the bush morning glory and the wild-sweet-potato vine are. The former has been successfully cultivated outdoors at The New York Botanical Garden, but for its best response it needs drier conditions than the climate New York provides. In suitable climates the bush morning glory is attractive for borders and naturalistic plantings.
Cultivation. Ipomeas of kinds commonly grown as perennials are usually raised from division of the roots, cuttings of firm, well-ripened shoots, by layering, and occasionally by grafting onto the roots of their own kind or other species. The last technique is often employed with I. horsfalliae, cuttings of which do not root readily and which is shy about producing seeds. Annual Ipomeas and those most frequently cultivated as such, and perennials at times, are raised from seeds. To facilitate germination it is advisable to cut a little notch in each with a file or to soak the seeds for several hours in concentrated sulfuric acid before sowing. They may be sown outdoors in spring where the plants are to remain, but in the north it is advantageous to start them earlier (six to eight weeks before the plants are to be set in the garden) indoors and to plant them out after the weather is warm and settled. By allowing the roots to become somewhat crowded in the pots before planting out it is thought that the vines are induced to come into bloom somewhat earlier.
Tender perennial kinds in the south are often wintered by cutting off their tops in fall and covering the roots with a heavy mulch. In the north the roots may be taken up and stored dry until spring, like those of dahlias.
As greenhouse plants, tender perennial morning glories are satisfactory in sunny locations and can be trained up pillars and other supports that permit them to be displayed advantageously. They thrive in ground beds, large pots, or tubs and revel in coarse, fertile, well-drained soil, with ample moisture and stimulating regular applications of dilute liquid fertilizer during their season of active growth. During the winter they are kept drier.
Seeds are sown in spring in a temperature of 60 to 70 degrees F. The seedlings are potted individually in 3- or 4-inch pots. When well rooted in these they are planted, five to seven together, in 8- to 12-inch, well-drained containers nearly filled with coarse, rich soil. Canes, wires, trellis, or brushwood must be provided for the stems to entwine and clothe. Watering is at first moderate, more generous when the pots or tubs are filled with roots. When this is achieved regular applications of dilute liquid fertilizer are helpful.
| Parson's Archive Home | Aggie Horticulture |