Guide to Container Sizes: Which Size Container Should I Use?
This guide to container sizes will help you answer the following questions when growing plants in containers: Which size container should I use? How much soil does my plant need?
Knowing which size container to use is crucial to gardening successfully in containers.
Different plants require different sizes for their roots, so it isn’t always easy to tell which size container you will need. Many young transplants and seeds are the same size initially but vary greatly once they mature.
A NOTE ABOUT CONTAINER SIZES:
- Container sizes are not standardized and often use different types of measurements.
- Sizes listed here are measured by the amount of soil they hold (dry-soil measurements).
- Choose the largest possible container for vegetables to give them access to more soil, food, and water.
- Generally, aim for the container to be as deep as it is wide. This provides the most room for the roots.
- Containers that hold less than 2 gallons of soil are not recommended for growing most vegetables to maturity.
Extra Small Container
Holds up to two gallons (.3 cubic feet) of soil.
Examples include: 8″ terra cotta or nursery pot, 2 gallon grow bag, and a 10″ hanging basket
Plants that grow well in extra small containers include: sage, rosemary, thyme, nasturtium, kale, green onions, basil, radishes, lettuce, chard, arugula, calendula
Small Container
Holds up to three gallons (.46 cubic feet) of soil.
Examples include: 10″ terra cotta or nursery pots, 3 gallon grow bag, and a 14″ hanging basket
Plants that grow well in small containers include: kohlrabi, carrots, beets, strawberries, dill, cilantro, celery
Guide to Container Sizes: Which Size Container Should I Use? (cont.)
Medium Container
Holds up to five gallons (.69 cubic feet) of soil.
Examples of medium containers include: five-gallon plastic bucket, 12″ terra cotta or nursery pot, and five gallon grow bag
Plants that grow well in medium containers include: beans, broccoli, cabbage, lemongrass, okra, potatoes, cucumbers, eggplant, peppers, ginger, turmeric.
Large Container
Holds up to ten gallons (1.5 cubic feet) of soil.
Examples of large containers include: 16″ terra cotta or nursery pots, and a 10 gallon fabric grow bag
Plants that grow well in large containers include: sweet potatoes, tomatoes, cantaloupe, watermelon
Extra Large Container
Holds up to twenty gallons (2.73 cubic feet) or more of soil.
Examples of extra large containers include: 18″ terra cotta pots (2.3 cubic feet of soil), 24″ terra cotta pots (3.8 cubic feet of soil), 20-gallon grow bags, and half wine barrels (4.3 cubic feet of soil)
Plants that grow well in extra large containers include: dwarf citrus trees, fig trees
My container gardening resources:
For more resources, I have several videos and blog posts that provide step-by-step guides, tips, and tricks for successful container gardening. I even wrote a book about container gardening, which covers everything from choosing the correct containers to harvesting your first crop. You’ve got this!
- Container Gardening for Beginners: 10 Steps for Success
- 20 Best Vegetables for Container Gardening
- Gardening in Grow Bags: 5 Tips for Success
- The Best Way to Water Containers
- Container Gardening Playlist on YouTube
To learn more about gardening in containers, read my book on this topic. Learn more about the book “How to Grow Your Own Food: A Beginner’s Guide to Container Gardening” in this post or purchase the book here.
I have a 100 gallon grow bag, should I use Ollas in them?
Yes, Oyas are a great option for grow bags, especially large ones like that. Good idea.
What size container for a 6 feet butterfly bush/ “Ruby spice” Pepperbush?
No smaller than 10 gallon.
What about the Arizona heat? My pots cook the plants. What helps that?
I put most of my smaller containers away for the hottest months of the year. If you need to garden in smaller containers, move them to where they receive morning sun and afternoon shade. Group them together to prevent direct sunlight on the containers.