University of Maryland Extension

Types of Containers

Containers can be temporary or permanent, practical or whimsical, artistic or utilitarian, expensive or free. When selecting containers, use your imagination and creativity, and know how much room your crops will need to grow to their full potential. You’ll also need to decide where and how to store the containers that are portable and used only during the growing season.

Choose the Right Container Size

Match container size to plant size, both the top growth and root system. Don’t squeeze large plants into small containers. If you restrict root growth too much, your plants won't grow well. It’s useful to consider both the depth and total volume of your containers.

  • Recommended potting media depth:
    • 4-6 inches: salad greens, Asian greens, mustards, garlic, radish, basil, cilantro, thyme, mint, and marjoram. (Salad greens and some herbs have shallow, fibrous root systems and are well-suited to shallow containers with a large surface area, such as salad tables or salad boxes.)
    • 8-12 inches:  beans, beets, chard, carrots, chard, cabbage, pepper, eggplant, tomato, squash, rosemary, parsley, lavender, and fennel.
  • Required pot volume:
    • 1-3 gallons: herbs, green onions, radishes, onion, chard, dwarf tomato or cucumber, basil.
    • 4-5 gallons: full-size tomato and cucumber, pepper, eggplant, beans, peas, cabbage, and broccoli.

Tips for Choosing Containers

container palate


Related information:
Cool container vegetable gardens 




  • Dozens of commercially produced containers can be purchased at garden centers and through mail order catalogs.
  • Dozens more everyday objects can be recycled or transformed into suitable containers- 5 gallon-plastic buckets, truck tires, hypertufa troughs, wooden crates, ½ whiskey barrels, nursery pots,  kids’ wading pools, plastic trash bags, and plastic storage containers.
  • Avoid treated lumber products and be aware that plastics not made for outdoors use can become brittle from exposure to the elements.
  • Except for the self-watering types, all containers should have holes or slits in the bottom to allow water to drain out.
  • Dark colors will create higher temperatures that could injure young tender roots and prevent the full development of a plant’s root system.
  • Containers made from porous materials (clay, ceramic, concrete, and wood) will dry out more quickly than containers made from plastic, or metal.
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