Growing tomatoes in containers is a great way for urban gardeners to have fresh, homegrown tomatoes, but planting them in the right size of container to get optimum growth is the key to a bountiful harvest. In this harvest, I’ll cover what you need to know about what size of pot, and what pot materials are best for your tomatoes.
What is the best size pot for tomatoes?
The best pot size for growing tomatoes is typically around 18-24 inches in diameter. This size allows for proper root development, moisture retention, and vigorous growth, ultimately leading to healthy plants and abundant harvests. For determinate tomatoes, choose a pot that is at least 5 gallons in size, and for indeterminate 10 gallons is the minimum. In general though, 15-20 gallon size pots is best.
Do tomatoes prefer deep or wide pots?
This is a bit of a trick question as tomatoes will grow just about anywhere you plant them. To the question of wide and shallow vs deep and narrow, the question is more about making sure the roots have enough room, and stability. If you plant your tomatoes in a shallow pot you will need to water more frequently. If you plant in too narrow of a container, then there is an issue of stability as a mature tomato plant can be very top heavy and blow over.
The best solution is to get containers that are wide and deep, maximizing both stability and root space. Personally, I prefer 15-20 gallon fabric grow bags for my tomatoes for just this reason.
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 like 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.
Follow Up – To follow up on these 5 gallon grow bags for tomatoes, they did work fairly well. They held up fabulously and performed well. The big downside was that with only 5 gallons of media, they did dry out very quickly which meant I had to be very diligent about watering, especially in the heat of the summer.
This year my garden bags are 15-20 gallons in size, just to reduce the frequency of watering.
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.
