Whether you are itching to start your vegetable garden or you have bedding plants to start for your flower displays, starting seeds inside your home gives both you and the plants a head start on the growing season. Seeds started early go into the beds larger and stronger than the same plants sown directly in the garden bed. Seedlings are most likely to fall to disease, and most diseases can be minimized or avoided completely indoors.
Sterilize all your seed-starting containers and tools. Mix 1-part bleach with 10-parts water and rinse the containers in the solution. Rinse in clear water and let dry.
Fill seed-starting containers with a quality seed-starting soil or soilless mixture. Make your own soilless mix by combining 1-part peat moss with 1-part vermiculite.
Moisten the soil mix thoroughly before planting. It should be moist but not soggy.
Sow two to three seeds per pot, planting each seed to a depth that is twice that of its width. Plant small seeds directly on the soil surface and cover with a 1/8- to 1/4-inch layer of vermiculite.
Cover pots with a plastic bag and place in a warm, 65 to 70 degree Fahrenheit, room to germinate. Remove the plastic bags once seedlings emerge, 7 to 21 days for most plant varieties.
Place seedling pots under grow lights so the top of the seedlings is 4 inches beneath the light. Place pots on top a stack of boxes to elevate them to the proper distance, and remove boxes to lower them as the seedlings grow to maintain the distance.
Keep the soil moist at all times but not soaking. Add a half-strength liquid fertilizer to the water once the seedlings produce their second set of true leaves---the third set the seedlings produce, as the first set is not true leaves but used to break the seed hull.
Transplant out to the garden once the weather is right for the particular plant---after the last expected frost date for most vegetables and flowers. Get seedlings used to outdoor conditions by placing them outside for a few hours each day for a week or two.