Ipomoea ternifolia var. leptotoma is a desert ephemeral native to Arizona and Mexico. It is horticulturally distinctive in its delicate, lacy leaves, which are divided into 3 or 5 narrow lobes; the rapidity with which it produces abundant flowers; and the striking violet-lavender color of its relatively large flowers.
Desert ephemerals are annuals that are adapted to brief periods of heavy rains and they are remarkable for the speed with which they flower and set seeds. Ipomoea ternifolia var. leptotoma, for example, will flower within a few weeks of germination. As the desert soil dries after heavy rains, the plant begins to die but even dying plants that have lost all their leaves will continue to produce flowers and set seeds so long as the stems remain green. Since desert ephemerals have no water-storing succulent roots, stems, or leaves, there is great urgency to set seeds before the last vestige of moisture is gone and extended hot and dry conditions return to the desert. The plants then lie dormant, in the form of seeds, awaiting the next period of heavy rain.
© 2010 Rufino Osorio.