Vegetable gardens are rewarding and productive but they can take up a lot of space. Many gardeners can't offer enough outdoor space or can't provide a plot with the right amount of drainage. Vegetable planter boxes, pots and containers make good alternatives for smaller-scale vegetable gardens.
Any container for vegetables must provide enough space and weight for the vegetable plants. Vegetables that grow in small containers may become root bound and fail to grow or even tip over.
An easy way to measure containers for vegetable growth is in litres. According to horticulturalists, any vegetable container should hold at least 13.5 to 22.5 litres (3 to 5 gallons) of soil to give the vegetable plants enough room.
Vegetables require deep, rich foundations, with plenty of space for their roots to stretch down. Most plants need containers at least 15 cm (6 inches) deep for full growth.
Width is another important consideration for vegetable containers, as the plants need room to spread and depend on the soil surface to gather sun, warmth and nutrition. Large plants like tomatoes and peppers get pots that measure at least 50 cm (20 inches) in diameter for full healthy growth.