Gallon Planting Containers

Gallon-Sized Containers

• One-gallon pots are the most common, according to the Washington State University Garden Center. Even though they are called "#1s," they hold about 3 quarts of soil. Most are round, but they can also be square, rectangular or octagonal. Most gallon-sized pots are actually about 6 inches wide by 7 inches deep.

Materials

• Plastic is the most common material used for containers in general. However, larger planters, such as 1-gallon containers, are often used to hold heavier plants such as large shrubs and trees. For this reason, larger containers are often made of heavier materials such as concrete, clay and wood. Such planters are often sealed to keep them from absorbing water from the soil, which can quickly dry out plants.

Plants

• Woody plants such as small trees and shrubs are often planted and sold in gallon pots. Starter perennials and small annuals are usually sold commercially in 3 to 6-inch square pots because they are more space efficient. Home gardeners, however, may choose to transplant them to larger containers. Shrubs are best for these sizes, as most trees are too large for a 1-gallon container.

Other Considerations

• Containers, no matter the size, need to have holes in the bottom for good drainage. Plants can quickly develop root rot and other fungal diseases if too much water remains in the soil. Many pots have a slight lip around the base that raises them a bit off the ground so that water can drain freely from the holes. Others have a water catch tray. These trays should be emptied immediately after the water stops draining so that the base of the plant is not sitting in water.