Garden containers come in a vast range of sizes, shapes and materials. Because of the range in choices, you'll need to plan carefully so you use the right garden container size for the application. Before deciding on a size, consider the use, location, material used, the plants and the environment.
The function of a garden container relates to its size. Container gardens, such as vegetable and herb gardens, can be grown in larger planters using companion gardening where multiple types of complementary plants are planted together.
The intended use of the garden container will help determine its size. If you are planting multiple plants in one container, it must be large enough to allow for adequate watering, root development and space. Starter containers are small because they are used for germinating seeds and growing seedlings for transplanting later. Terrariums are small garden containers used to grow entire microgardens. Sod or hay planters act as both container and sustainable medium for plants, but must be large enough to support the plant life while small enough to hang because they cannot sit on surfaces.
Take the type of plant into account when choosing the container size. Plants can quickly outgrow smaller garden containers; when this happens the roots begin to get crowded and begin losing access to adequate airflow, moisture and nutrients. Small bush plants such as peppers, beans or roses can be grown in 5-gallon containers; herb gardens can be grown in an 18-inch diameter container. The depth of the garden container also matters because some plants require deep root systems such as tomatoes, potatoes, iris or smaller evergreens; other plants can use shallow containers such as radishes, herbs or grass.
The location of the garden can also play a factor in the garden container size. Hanging gardens cannot use larger containers because of the weight. Indoor gardens also use small or medium containers because of space restrictions. Outdoor gardens can have a range of sizes, depending on the plant and the container material being used. Greenhouses can use a variety of garden container sizes from large planters on the ground to hanging planters and starter containers, depending on the plant and the age of the plant.
The garden container size may be determined by the material used. Items such as terracotta and stone are heavy, therefore will require smaller sizes for mobility; larger sizes are suitable for permanent landscapes or larger plants and trees. Plastic containers can be any size, although they can retain water. Because of this, the size may cause a problem when the soil is drying out because the more soil there is, the longer it takes to completely dry out. Plastic is lightweight, but becomes heavy when used in larger sizes because of the soil it contains. Because they're lightweight, smaller containers can be blown over by wind or washed away by fast water flow.