Whether you're limited on space, the soil around your home is undesirable, or you just want to make getting outdoors and "gardening" easier, growing tomato plants in a container or planter is often a good solution. Tomatoes respond quite well to being in containers and you can often avoid common diseases which are caused by overcrowding and limitations of air circulation. To grow a container tomato you'll need to have an area of full sun to set the planter and room and supports for the tomato plant to grow upward.
Set the container in your desired location where your plant will see six or more hours of direct sunlight per day. Cover over the bottom of the container with gravel and then fill the planter with soil up to an inch or two from the rim.
Stick a garden stake into the soil and push down until you feel contact with the gravel. Dig a hole in the soil next to the stake as big as the pot your tomato seedling is in and transfer your tomato plant from the seedling pot to the hole.
Firm up the soil around the tomato and water the plant well to wet the soil. Water the container anytime it feels dry an inch below the surface, watering more frequently in the summer months if rainfall is lacking.
Use a low-nitrogen fertilizer following the instructions on the packaging as frequently as the directions suggest. Stop using the fertilizer, however, once you see the first small, green tomatoes starting to form.
Tether the main stem of the tomato plant to the stake as it grows by using plant ties to loosely hold the plant to the stake as it needs support. Typically you should only need to tie every 9 to 12 inches.
Harvest from your plant whenever the tomatoes are ripe and let go of the vine easily when pulled. The more you harvest, the more productive your tomato plant will be.