Gardening food crops in containers has numerous benefits. It allows you to keep plants intolerant to heat and cold indoors as needed, create micro-climates for demanding crops, grow food without risk of lead contamination, and tend an entire garden in a limited space. Maintaining a container garden can be costly and demanding; but it needn't be. The best feature of container grown food is, after all, ultimate flexibility.
Because of the infinite variety of container gardens, a single tutorial will not suit all gardeners. Instead, consider the list of common steps and guidelines below.
Choose your location.It is recommended that plants stay close to the gardener. This will allow for better observation, easy access, and a greater likelihood of involvement. Plants kept close to a wall exposed to sunlight (typically the south-facing wall) could both utilize the extra hours of light and serve to cool the building by providing shade and moisture. However, it is always best to keep plants out of the lead-dust "Drip Zone" created by deteriorating building materials and paint. To reduce the risk of lead in garden soil, place plants about six feet away from the walls of older residences, driveways and roads.
Know your environment. The standard rule for fruit and vegetable gardens is to allow plants about six hours of sunlight. If the location of your container garden will receive less than this, you will need to make some accommodations. You may need to opt for different crops, devise a method by which you can move the containers during the day or redirect sunlight. You should also consider wind blocks if your plants will be exposed (as in roof-top gardens) or mulching if the plants are likely to be battered by extreme heat from sources like hot concrete or long periods of direct sunlight.
Select crop varieties with care. Not all fruits and vegetables will perform their best in a container. Look for plants with smaller root systems, or plants that are known "patio" or container varieties. Even if you choose to plant a crop that prefers more depth or surface area, it may still produce a considerable amount of food while growing in a small space; the amount harvested could just be notably less.
Prepare the containers. Containers vary greatly. They may be self-watering, doubled, heat-retaining or releasing, hanging, stacking, temporary, tiny or enormous. No matter what type you choose, it must meet two basic requirements; it should be clean and it should drain well. To wash a pot, use soap or a vinegar solution and, after a thorough scrubbing, rinse very well. Every container that will encase roots and soil should have a draining mechanism. Most often, this will simply be a few holes at the container's base. Puncture holes yourself if needed. Once a drainage system is in place, no further aid is required. The soil will drain best if nothing obscures its connection to the drainage site.
Pot your seeds or transplants. Moisten the soil and allow to drain somewhat. Sow seeds directly or install transplants with care. Many plants can coexist in a single container if the growing space is ample, though you should always be aware of plants' light, water and soil requirements to ensure compatibility. Water lightly once seeds or transplants are in place.
Monitor and hydrate. Fruits and vegetables are often over-watered by beginner gardeners. However, plants in containers are more likely to dry out due to higher soil temperatures. The soil should never be soggy or emit a foul smell, nor should it become dry or hard. Be watchful so that you can maintain a healthy balance; keeping the soil moist and adjusting your containers if the plants show signs of decline. You should also take action if pests or disease are apparent. While many pests and diseases will devastate only one type of crop, some fruits and vegetables are related and the problem could spread quickly. Afflictions such as these are usually a good indicator that the plant is not adapting well to its environment or inputs. Proper management and care can save a garden, so act immediately.
Take notes. Keeping a log of garden activity is always a good idea; saving you considerable guesswork in the future. Details that should be recorded are: plant varieties, soil type, container type, general location, dates of fertilization, information concerning any disease or pest outbreak, as well as successes and failures. It would also be wise to record, as farmers do, the size of harvest. You can use this record in the following growing season to troubleshoot or better select future crops and components.
Harvest frequently, store wisely. Leaving fruit attached after it has ripened could have detrimental effects. Plants may halt production entirely, or the crop could dry, soften, spoil or burst. Plants that do not produce fruit must also be harvested in a timely matter. While there are a few crops that stay fresh or gain quality by being left outside while ripe (kale, broccoli and roots, for example) all vegetables will eventually develop off-flavors or textures over time. Fruits and vegetables are best enjoyed fresh, but there are many methods by which a gardener can preserve their crops. Consider dehydrating, canning, freezing, fermenting, curing or placing in a root cellar. If you know that you will be harvesting an abundance, plan ahead so that you preserve food at its flavor peak, rather than allowing it to become blander and less nutritious between picking and preserving.
End your season responsibly. When the weather cools and/or some plants have become spent, compost the organic matter and invigorate the potting soil with fresh material. Cover soil so that it is not exposed to the elements between plantings. Bring delicate perennials and biennials indoors or to a warmer spot with protection from the wind.
With patience and care, the above suggestions should serve to help you plan and achieve a bountiful container garden. Remember that every farm and garden has its setbacks, but that each successive season is generally more fruitful and well executed than the last. In time, you can develop a thorough understanding of natural cycles, plant health and good practices just by tending a small, contained garden.