Morning glories (Ipomoea spp.) are fast-growing, annual flowering vines that many gardeners start indoors to get a head start on the growing season. These tender plants cannot tolerate cold and thrive only in warm conditions, which makes timing the transition from a sheltered indoor environment to the garden crucial. Successfully establishing these vines requires careful observation of the seedlings, a measured acclimation period, and gentle handling during the final move. The goal is to move the young plant only when it is structurally mature and the outdoor environment is reliably warm enough to support growth.
Determining Seedling Readiness
The first indication that your morning glory seedlings are ready to leave their indoor tray is the development of their first set of “true leaves.” The initial pair of leaves, called cotyledons, sustain the plant until the true leaves, which resemble the mature vine’s foliage, appear and begin photosynthesis. Seedlings are typically ready to be moved once they have developed at least two to four true leaves and have reached a height of approximately three to six inches.
The outdoor environment must also meet specific criteria, as morning glories are sensitive to cold and frost. It is necessary to wait until all danger of frost has completely passed in your planting zone before considering a permanent move outdoors. These heat-loving plants require warm soil to thrive, so the outdoor ground temperature should be at least 60°F or higher for optimal establishment and root growth. Nighttime air temperatures should also remain consistently warm, well above 50°F, before the seedlings are transplanted.
Acclimating Seedlings to the Outdoors
Before planting them directly into the garden, morning glory seedlings must undergo a mandatory transition known as “hardening off.” This process gradually prepares the tender, indoor-raised plants for the harsher elements of the outdoor world, such as direct sun, wind, and fluctuating temperatures. Skipping this step often results in severe transplant shock or complete failure of the plant.
The acclimation should begin about seven to fourteen days before the intended transplant date. Start by placing the seedlings outside in a shaded, sheltered spot for one to two hours during the warmest part of the day. On subsequent days, slowly increase the duration of their outdoor exposure by an hour or two, while gradually introducing them to more direct sun.
By the end of the hardening-off period, the seedlings should be able to tolerate full sun exposure for the entire day. It is best to bring them back inside or provide temporary cover at night until the final move, especially if evening temperatures are still cool. Throughout this transition, maintain consistent moisture in the soil, as the plants will dry out faster when exposed to the outdoor air circulation and sun.
The Transplanting Process and Immediate Care
The physical move should be planned for a calm, overcast day or during the late afternoon to minimize the immediate stress of intense sunlight. Prepare the permanent planting location, which should receive at least six hours of full sun and have rich, well-draining soil. Dig a hole that is slightly wider than the seedling’s root ball, loosening the surrounding soil to encourage root spread.
Morning glories have fragile roots, so gentle handling is necessary to prevent damage and minimize transplant shock. Carefully remove the seedling from its container, keeping the soil surrounding the roots intact as much as possible. Plant the seedling at the same depth it was growing in its original container, ensuring no soil is piled up around the stem.
Space the young vines at least six to eight inches apart to allow for mature growth and adequate air circulation. Immediately after planting, thoroughly water the area to settle the soil around the delicate roots and remove any air pockets. Providing a trellis, fence, or other sturdy structure at the time of transplanting gives the twining vines something to climb right away.