Whether you are growing a vegetable garden or planting ornamental plants, transplants give you a head start on the gardening season. Many summer annuals, including most vegetables, benefit from being grown indoors so that they are well established before being exposed to the elements. Planting in pots and later transplanting to the yard or field also prevents pests from eating seed or tearing up seedlings. Transplanting must be done properly to prevent damage to the plants and to prevent shocking the plants by sudden exposure to wind and sun.
Set the plants outdoors in a protected area, such as a patio, beginning seven to 10 days before you plan to transplant them outside. Leave the plants out during the daytime and bring them indoors at night. Gradually move the plants into direct sunlight during this time. This "hardens off" the plants so they are better able to handle outdoor conditions after transplanting.
Water the soil in the pots so the excess moisture drains from the pots one or two hours prior to transplanting. This loosens the soil and makes it easier to remove the plants from their pots.
Lift transplants from plastic pots by their leaves. For well-rooted transplants, place your hand over the top of the pot with the stem of the plant sticking up between your forefinger and middle finger. Do not apply pressure to the stem at all. Turn the pot upside down so that your hand is supporting the soil, then lift the pot off the root ball.
Tear off the rims of peat pots and plantable cardboard pots rather than removing the plants from these containers. The rims of these pots must sit beneath the soil in the garden or they'll wick moisture away from the plant's roots.
Dig the planting hole to the same depth as the root ball or slightly deeper than the peat pot, depending on which is applicable. Set the plant in the hole so it is at the same depth it was at in its pot, or set peat pots so the rim of the pot is ¼ inch beneath the soil surface. Refill the hole around the plant with soil.
Water the planting area thoroughly after planting so the soil is moist to at least an 8-inch depth. This collapses any air pockets in the soil around the plant's roots.