Hybrid seeds are configured by human hands, rather than a naturally forming heirloom or original seeds. Most times you cannot save the seeds from a crop of hybrids, replant them and grow a healthy crop of tomatoes. Heirloom seeds can be saved and replanted endlessly. The advantage to hybrid tomato seeds is that there are all different types, requiring different growing periods and conditions. This means there are a lot of choices, and almost anyone can find a tomato seed that matches his or her growing season. Start the seeds indoors six to eight weeks before the last expected frost in your location.
Use seeding trays from your local garden center if you are planting a lot of hybrid tomato seeds. For just a few plants, use peat pots, used plastic containers (from yogurt, sour cream, cottage cheese) or paper cups.
Fill the seeding containers with commercial potting soil up to approximately ¼ inch from the top.
Make an indentation in the soil with the end of a pencil, about ¼ inch deep. Drop a hybrid tomato seed in each hole--one per container. Cover the hole with potting soil.
Mist the top of each seeding container to moisten them. Do not overwater, making a sopping mud of the soil. Mist the soil each day. The seeds must be kept moist until they germinate.
Place your seeded containers on a tray and put them in a sunny window or under grow lights, in a room with a temperature of 75 to 90 degrees Fahrenheit. A sheet of plastic wrap over the seeded container will help keep the soil moist and warm, but must be removed as soon as germination takes place.
Move the seedlings to a cooler location of 60 to 70 degrees Fahrenheit after germination. The seedlings must still be located in a full-sunlight location. Water them when the soil begins to appear dry.
Place the seedlings outdoors to acclimate them, once the last frost has passed and there are two to three sets of leaves on the plants. Start by leaving them outdoors a couple of hours the first day. Leave them out longer each day until they have been outdoors an entire 24 hours. Start them in a protected location, such as a covered patio, and ease them out towards the garden area. This process is called "hardening off" and takes about a week.
Prepare the outdoor soil by breaking it up, 6 to 8 inches deep, with a shovel and mixing in compost. This will create a nutritious, well-drained soil.
Space your hybrid tomato plants according to the seed package directions; 24 inches apart is average. Every type of plant will require a differing amount of lateral space to grow properly. Dig a small hole in the garden soil, deep enough so the top of the seedling soil will set at the top of the ground. Compact the soil around the plant to give it structure. Water the seedlings as the soil begins to dry. This may be every day if temperatures are already starting to warm.
Fertilize your tomato plants when you see the fruit forming. Offer additional doses of fertilizer every ten days thereafter until the growing season is over.