Transplanting simply means moving a rooted plant from one place to another. If you prick out tiny parsley seedlings from a flat into individual pots, you’re transplanting. If you move tomato plants from your windowsill into the garden, you’re transplanting. And if you decide to move the big forsythia to the backyard, you’re transplanting, too.Pour warm water onto the soil mix, and let it sit for an hour to soak in. Moist potting soil prevents seedling roots from drying out.
Carefully dig out either individual seedlings or small groups of seedlings. A Popsicle stick makes a good all-purpose tool for digging, lifting, and moving tiny plants. A tablespoon or narrow trowel works well for larger transplants.
Hold each seedling by one of the leaves, as shown, not by (or around) the stem: You could crush the tender stem, or if you grasp the stem tip, you could kill the growing point and ruin the seedling’s further growth.
For very young seedlings, poke small holes into the soil mix with a pencil. For larger seedlings, hold the plant in the pot while you fill in around the roots with soil. Firm the soil gently with your fingertips.
Return the seedlings to the window, light rack, or cold frame. If seedlings wilt from the stress of transplanting, mist lightly with water and cover loosely with a sheet of plastic wrap. Keep them cool and out of direct sun for a day or two, them remove wrap and return to the light.
Keep soil lightly moist but not soggy by pouring water into the tray holding the containers. Feed regularly with a weak solution of water-soluble organic fertilizer.
As the plants grow, pinch or snip off any extra seedlings, leaving only the strongest one.