Whether you are caring for tomato seedlings until you are ready to transplant them outside or you want to try growing a plant to maturity inside, proper care is necessary for the plants to survive and thrive. Tomato plants are warm-weather vegetables that require at least eight hours of sunlight a day. Providing these conditions indoors can be challenging. Keep you tomatoes healthy until transplanting or harvest time with proper planning and equipment.
Place your tomato plant in an area where it receives at least eight hours of sun a day, preferably in a south-facing window. If you don't have a suitable window, place the plant under grow lights so that the top of the plant is 6 inches away from the light source. Leave the lights on for 14 hours a day.
Set the plant in a room that is at least 75 degrees F. Avoid areas that are prone to drafts, because these may cool the plant or dry out the soil quickly.
Stick your finger in the soil two to three days, and if the top 1 inch of soil feels dry, water your tomato plant until the excess moisture drips from the bottom drainage holes on the pot. Empty the drip tray after watering.
Fertilize tomato plants every two weeks with a soluble, general-purpose fertilizer. Follow label instructions for exact application amounts, because these differ between brands. Follow each fertilizer treatment with a thorough watering.
Stake tomato varieties that grow taller than three feet. Push the stake into the soil until it touches the bottom of the pot. Tie the plant loosely to the stake every 6 to 8 inches, placing the tie above flower clusters, not below them.