Grow your plants by starting seeds indoors for the best variety. Most varieties, especially heirloom and organic types, are not available from local nurseries or garden centers. Purchase heirlooms and organics from seed catalogs or online. For the best results, choose high-quality seeds from reputable sources, advises Erv Evans and Frank A. Blazich of the North Carolina State University Extension. Only buy enough seeds to grow for that year, as older seeds germinate poorly.
Soak a bag of potting soil with water. Sit the bag, overnight, in a bucket or sink to allow the water time to fully soak in. By morning, you should have moist soil.
Scoop moist potting soil into an indoor pot and fill until about three-quarters full. Select a pot large enough to grow the plant. Read the instructions included on the back of the seed packet. Pay particular attention to the spacing requirements. For example, if the seed packet advises spacing seeds 2 inches apart, plant two plants in a 6-inch pot.
Make shallow holes with the tip of your finger in the soil. If growing two plants, make two holes in the middle of the soil, spaced according to packet instructions.
Push one or two seeds into the soil, 1/4 to 1 inch deep, as directed by your seed packet instructions. Pack soil lightly over the top of the seeds.
Keep the pot in a warm location, away from sunlight, until seedlings emerge. Ideally, use a location that maintains a consistent 70 to 80 degrees F temperature. Move the pot to a window that receives full sunlight, usually a south-facing window, after seedlings emerge. Rotate the pot weekly, moving it slightly, to give all sides of the plant an opportunity to receive full sunlight. While most plants require full sunlight, some plants may prefer a little shade. Place shade-loving plants away from the window, on a countertop or other surface where the plant receives some amount of sunlight.
Trim seedlings after they have grown two leaves. Cut the weakest seedlings from the plant. Cut the seedlings at soil level with a pair of clean, sharp scissors. Leave only one seedling per plant.
Water the plant daily with a gentle spray of water. Skip watering if the plant appears moist.