Growing tomatoes on a balcony is very doable and will provide fresh produce throughout the summer. The key to container-grown tomatoes in small spaces is choosing the right type of tomato that will not grow too large and become hard to manage. Determinate varieties are the preferred tomatoes for containers, since they stay more compact, reaching 1 to 3 feet tall. Some good choices include Celebrity, Early Girl, Sweet 100 and any type of cherry or grape tomato.
Select a 5-gallon container with drainage holes in the bottom and add a layer of coarse gravel into the bottom. A 5-gallon bucket works well for growing balcony tomatoes and can be moved easily with the handle. Set the container on a drip tray to catch any water.
Fill the container with potting soil and add a handful of compost, mixing well. This creates a well-draining soil that is crucial for the health of the tomato plant.
Dig a hole that is about three times as deep as the height of the rootball. Add a handful of bone meal to the hole to provide the plant with needed calcium.
Clip off the bottom two sets of leaves on the tomato plant, leaving only one set on the top. Place the plant deeply in the hole, so the top set of leaves is right above the ground's surface. Fill in the hole with soil and tamp down well around the plant.
Water the newly planted tomato well, until the water drains out through the bottom. Keep the tomato watered consistently every day so the soil stays moist. Inconsistent moisture can lead to cracked fruit and limited growth of the plant. Empty the drip pan each day or as needed.
Feed with a fertilizer designed for tomatoes, such as a 15-30-15, which has a higher amount of phosphorus necessary for abundant fruiting. Use a time-released formula and avoid one that has too much nitrogen, which will encourage more vegetation, but less fruit. Fertilize right after planting and every two weeks after, stopping as soon as the tomatoes begin to appear.
Stake your plant with a wooden stake or a tomato cage that will fit the container. This gives support to the plant so it does not fall over and break stems. Use twine to attach to the support and retie as the plant grows. If you are growing short determinate tomatoes, this step might not be necessary.