Knowing The Right Pot Size For Tomatoes Is Critical
One of the most popular urban gardening choices is tomatoes, but what pot size do you need for tomatoes? A common mistake when growing tomatoes in containers is going too small.
Tomatoes are heavy feeders that have extensive root systems. Going too small means stunted plants and fewer tomatoes in the long run.
Sticking with more conventional pots, most urban gardeners choose containers of ~5 gallons/19 liters for full size tomatoes. Smaller dwarf or determinate tomatoes can be successfully grown in smaller containers down to 3 gallons.
Remember that tomatoes love moisture and are not happy if they dry out. Too small of a pot for your tomatoes means that it will not only get root bound, but dry out, but not hold enough moisture to keep the plants happy.
Materials For Tomato Containers
For now we will avoid the more exotic tomato containers (upside down, hydroponic and so on) and focus on the more traditional pots for tomatoes. Once you know the pot size for tomatoes, you have to think materials. Here are a few of the most common.
Terracotta Tomato Pots
Terracotta is a traditional material for gardening. My experience is that for one, terracotta pots big enough for tomatoes tend to be expensive, heavy and prone to breakage. If you live in a part of the country that freezes during the winter, they need special treatment to survive. Additionally terracotta tends to wick moisture out of the soil and dry the plants out faster than other materials.
Glazed Ceramic Pots
More durable than terracotta and less prone to drying out, glazed ceramic pots are a better choice in my book. The only issue with them is that they are heavy and generally expensive considering the size of pot needed for tomatoes.
Plastic Tomato Pots
A common choice for tomato gardeners, plastic containers are affordable, durable, and lightweight. 5 gallon buckets with holes drilled in them work perfectly fine if you are not worried about aesthetics. Of course you can always buy more attractive ones. The only concern with plastic pots is making sure they drain adequately. Tomatoes like water, but don’t want to be water logged.
Wooden Containers For Tomatoes
Whether they are purpose built cedar planting boxes or old half barrels, wooden containers work well for tomatoes. The downside to wood tomato containers is that they generally only last a few seasons before breaking down.
Concrete Containers
Concrete is a solid choice for a tomato pot. Coming with that of course is a whole lot of weight. Of all the choices, concrete pots are the most durable — and the heaviest, so plan to place them in a permanent spot. Large sizes can be costly.
Fabric Grow Bags For Tomatoes
In my book, fabric grow bags are the best way to go for urban gardens and growing tomatoes. Considering the pot size for tomatoes, grow bags are light, breath and drain well and are inexpensive. They last several seasons and don’t rot.

This year I am testing out 5 gallon square grow bags for my tomatoes. I’m liking the square shape of these though I’m wondering if the corners will be a weak point. The hope is that I can get more soil in around each plant in the same amount of space.
Final Thoughts On What Pot Size For Tomatoes
Whether you go with a traditional material or something more advanced like fabric tomato pots, bigger is better. Of course you will need a sunny location for them and plenty of fertilizer.
When it comes to growing tomatoes, whether in a full size garden or an urban one, growing tomatoes is essentially easy, but growing AMAZING tomatoes is a science unto itself.