Containers require little space and are a good choice for those with little or no yard space. They are easily accessed, requiring less time to care for than a vegetable or flower patch. Containers allow the elderly or those with limited mobility to enjoy gardening. While containers may initially cost more than traditional modes of gardening, they are generally less expensive overall, according to West Virginia University.
Almost any plant can be grown in a container, although flowering annuals and houseplants are most often grown. Vegetables, such as tomatoes, eggplant, lettuce, onions, cucumbers and carrots, are often grown in containers. Herbs, perennials and bulbs brighten patio areas. Even small shrubs, trees and vines are planted in containers.
Any container can be used for planting, including old boots, a well-used wheelbarrow or recycled pottery. The most important criteria in selecting a container is that it has holes to provide good drainage to the plants. Plastic pots are inexpensive, but may crack and fade in the sun. Terra cotta pots are porous and lose moisture quickly. Glazed ceramic pots, while more expensive, retain moisture and are nonporous.
Small pots may be suitable for some herbs and small annuals, but they dry out quickly and constrict a plant's growth. Additionally plants must be repotted fairly soon. Starting out with a large pot, at least 1 gallon in size, allows plants to develop healthy roots. Additionally, very large pots, 16 inches and larger, can be planted with several varieties in the same pot. More growing medium is required, but the cost is probably less overall than using several small pots.
Most plants have root systems about the same size or slightly larger than their top growth. The mature height and width of a plant should be considered when choosing a pot. Additionally, some plants don't transplant well. For example, a small tree or shrub is difficult to transplant, so choosing a large enough pot to begin with is the better choice. Root vegetables, such as carrots, potatoes and fennel should be planted in deep pots to accommodate the roots. Five-gallon containers are appropriate for most vegetables, advises Texas A&M University.
Plants in containers dry out quickly and should be checked daily in hot weather. Additionally plants that have outgrown their containers must be transplanted. Symptoms include top growth that is out of proportion with the container size or roots protruding out of the drainage holes. Plants grown in containers that are too small will have stunted growth and unhealthy roots.