If you generally purchase tomato plants and raise them, then you know that the choices are limited to the choice the garden store carries. Growing tomatoes from seed opens your lawn up to an overwhelming range of tomatoes in dozens of colours, flavors and sizes. Growing tomatoes from seed takes more work than growing pre-established plants, but it is often less expensive — especially if you use recycled containers, like cardboard egg cartons, to germinate them.
Cut the lid off a a clean, empty cardboard egg carton.
Cut out each person egg cup to create individual planting cups. Avoid leaving the egg cups connected, as they will be harder to separate afterwards when they include plants.
Set the egg cups at a greenhouse tray with a lid or in a shallow plastic container. Line them up so they fit snugly at the container without a lot of space to move around or spread outside.
Fill each cup with a moist soilless peat or seed-starting mix.
Place one tomato seed about 1/8 inch deep into each egg cup. Press down on the ground with your hands to bury the seeds.
Water gently so that the soil gets completely moist, but is not wet or soggy. Expect the paper egg cups to absorb water and soften.
Cover the container with a clear plastic greenhouse lid or with a loose layer of plastic wrap to keep heat and moisture in. Set them in a warm spot that remains at least 65 degrees Fahrenheit, like a countertop. Avoid putting them alongside a sunny window as they may get too hot.
Water the seeds and seedlings only sufficient to keep the soil moist, as required.
Transplant the seedlings when they have four true leaves. Transplant them into to 3- to 4-inch pots or recycled plastic cups with several drainage holes cut out of the bottom. Use a spoon in the event the paper pots are now too soft and set the entire egg cup — paper and all — into the container. Bury the seedling heavy enough so at least half the stem is covered, since this stem will put out roots and also help build a stronger plant.
Repot again into 1 gallon jugs when the plants look healthy and strong and reach at least 6 inches tall. Start putting them outside for a few hours each day to strengthen them and get them used to outdoor conditions. Bring them in at night. Keep them in the gallon jugs till May or June if you intend to put them into your lawn or into their permanent container.