When a seed germinates, the tiny plant breaks through the surface of the soil and begins to establish roots underneath. Seeds planted in a seed tray indoors may produce seedlings, provided the soil has been kept moist and warm. When you see the seedlings emerge, remove them to flats and add fresh potting soil Allow them to grow to approximately 3 inches in height before preparing them for transplant.
Harden off your seedlings to acclimate the plants to the outdoor climate. After the danger of frost has passed and the temperatures are rising, set your flats with the seedlings outdoors during the warmest part of the day. Bring them in before the temperature drops.
Leave the plants out longer each day, finally leaving them out overnight after two to three weeks of exposure. If the plants remain upright and appear healthy, they're ready for transplant to the garden. If the seedlings show signs of distress, wait until the night temperatures rise before leaving them outdoors overnight again. The process of hardening off may take up to two weeks.
Prepare the garden site for the transplants during the hardening off process. Add compost or organic fertilizer to the garden beds or rows, turning the soil to keep it loose. Water the garden beds or rows the day before you intend to transplant your vegetable seedlings.
Bring your flats out to the garden. Dig a hole where you intend to plant your first seedling. Make a hole deep enough to sink the seedling into the soil so the roots and the first 1/2 inch of its stem is beneath the soil line, approximately six inches.
Gently loosen the first seedling from the flat with the tip of a spoon or Popsicle stick and lift the seedling out. Keep the soil and roots intact as much as possible. Set the seedling into the hole. Fill the hole with the displaced soil.
Continue to plant the seedlings, selecting only the healthiest plants. Add the discarded seedlings to your compost pile.
Gently water each new transplant using either a watering can with a slender spout or irrigation drip system. Do not allow a water stream to wash over the new plants as this may break the stems or send the plants into shock.
Cover the fresh transplants with row covers to reduce pest infestation. Remove the row covers when the seedlings reach the height at which their tops are touching the tops of the row covers.
Continue to care for your vegetable plants by practicing consistent watering habits and adding fertilizer as the plants begin to flower. Follow the manufacturer's directions for your fertilizer of choice.