If you live in an apartment, you may feel limited in your opportunities to garden. But this does not need to be the case. A sunny balcony can provide the perfect opportunity to grow vegetables in containers. Almost any plant will grow well on a balcony provided that it is given enough soil to support the roots. Plants with an upright habit will adapt well to containers. Even vegetables that vine can be grown in containers, provided that you give them enough space to spread out.
Choose a lightweight soilless potting mix for your vegetables. Because soil in containers dries faster than soil in the ground, many potting mixes have moisture-retaining crystals to help hold water for longer periods of time. Potting mixes also have materials such as vermiculite and perlite to help lighten the soil and improve drainage.
Select containers that are large enough to support your plants. Vegetables with wide spreading habits, such as beefsteak or better boy tomatoes, require containers that hold at least 5 gallons of soil per plant. Potatoes can be grown in a garbage can or a 36-qt. bag of potting soil that has been cut open. Smaller plants such as radish or green onion can grow well in shallow trays because they do not require as much space. In addition, plants should fill a container completely. If a container has too much soil, it will retain water, which will promote root rot in a plant.
Purchase transplants to start your container garden, or start seeds indoors in a sunny windowsill eight weeks before you can move your containers outdoors. Miniature and patio vegetable varieties of vegetables are well suited for balcony container gardens because they have smaller space varieties than larger vegetable plants. For example, cherry tomatoes or dwarf varieties such as tiny tom will take up less space than full-grown tomato varieties such as beefsteak. These varieties will grow well in hanging baskets or window boxes mounted to balcony rails. Miniature plants also have smaller container and soil requirements, which make them easier to care for. Herbs such as parsley, basil and mint are also good candidates for container gardens because of the plant's compact growing size.
Check your containers daily and water them whenever the soil seems dry. The soil in vegetable containers should remain as damp as a wrung-out sponge. Add a liquid fertilizer (10-20-10) to the water in a ratio recommended by the fertilizer package to feed the plants. Fertilizer ratios will vary depending on the fertilizer manufacturer.
Harvest vegetables when the crops hit the peak of maturity.