Container gardening is a method of growing plants when the soil conditions outdoors are inadequate, there is not enough room for a garden or you wish to grow plants indoors during the winter. Building a successful container garden requires choosing the right containers, the best growing medium and providing the extra nutrients required for a plants healthy growth.
Most containers will work for growing plants, but containers do require drainage holes at the bottom to release extra water from the soil. Most plant containers from garden centers have drainage holes at the bottom. Containers made from recycled jugs may require the addition of drainage holes. Iowa State University recommends drilling 1/4-inch holes at the bottom of the container. A 1/2 inch of gravel, small stones or pieces of broken clay pot should be placed at the bottom of the container to prevent dirt from escaping the bottom
A lightweight growing mix is required for container gardening to prevent compaction and allow easy root movement. West Virginia University discourages the use of soil from an outside garden as it will likely be too heavy. You can buy packaged potting soil from garden centers, but when building a large container garden this may be too expensive an option to consider. Mix your own container medium using 1 part peat moss, 1 part garden loam, 1 part clean sand and a complete, slow-release fertilizer. The pH of the container soil requires checking with a pH testing device, and should read around 6.5.
Nutrients in container soil are quickly used and must be replaced with a fertilizer. A water-soluble fertilizer requires application once every two to three weeks. A fish emulsion should be applied occasionally to add additional trace elements not found in many manufactured water-soluble fertilizers.
Soil in container gardens dries out quickly and needs consistent watering. Some containers will need daily, if not twice daily watering. Over watering is just as damaging. Water should be applied until is runs out of the bottom of the container. If there is a drainage tray placed under the container, it should be drained after the soil has had an opportunity to absorb as much of it as it will hold. Test the moisture of the soil by touching the surface to see if it is dry, or tapping the side of the pot. A hollow sound indicates it's time to water the container.