What Size Grow Bag for Tomatoes is Ideal? – Best Suggestions

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Last Updated on April 6, 2023 by Griselda M.

What size grow bag for tomatoes is appropriate to be used? You may have limited garden space, and you are considering using grow bag for your tomato plant. Using grow bags to cultivate tomatoes is a great way of utilizing the little space you have to grow tomatoes.

It is not a new thing to grow tomatoes in grow bags or even containers or pots. Tomato is an excellent plant that can be easily grown in grow bags.

So, if you are short of space or you don’t have a garden or lawn, you shouldn’t worry because you can take advantage of grow bag to grow your tomato plant.

But what is the ideal grow bag to use for tomato plants? This is the question we will be answering in this post, so if you’re curious to learn more, then continue reading for some insight on the subject.

What Size Grow Bag for Tomatoes?

The ideal grow bag size to use for your tomato plant should be between 8 inches (15 to 17 cm) and up to 14 inches (30 cm or bigger). But generally, a minimum of 10 to 15 inches diameter grow bag is appropriate for growing tomato plants. Then the grow bag can be at least 8 to 12 (20 to 30 cm) inches deep.

Or, we can say a 10-gallon grow bag is ideal for determinate tomatoes. Then, for indeterminate tomatoes, a 20-gallon grow bag should be used. Between 5 to 7 gallons of grow bag space is ideal for smaller tomato varieties; such as cherry tomatoes or compact patio tomato varieties.

Can Small Grow Bags Be Used for Tomatoes?

Even though it’s possible to grow tomatoes in smaller grow bags, we will, however, advise you against doing so. This is because the tomato plant can become overcrowded, and this can affect the development of roots as well as nutrient and water absorption.

Using small grow bags for tomatoes can give rise to stunted growth, coupled with a poor yield.

Read more about Problems With Self-Watering Pots – Top 5 Common Problems

What Are the Factors That Determine the Grow Size Bag for Tomatoes?

The size of grow bags usually ranges from 5 gallons, and reach up to 1000 gallons. From the explanation above about using small grow bags for tomatoes, it is only logical to try and avoid using this size.

But do you know how you can determine if a grow bag is too small for the type of tomato variety you’re growing? Well, you can use the factor below to consider how you can go about choosing the ideal grow bag size for tomatoes.

·         The variety of tomatoes – What size grow bag for tomatoes

Ideally, tomato varieties such as cherry tomatoes require smaller grow bags. The bigger tomato variety, such as beefsteak tomato, will require larger grow bags.

VIVOSUN 5-Pack 10 Gallons Heavy Duty Thickened Nonwoven Fabric Pots Grow Bags with Strap Handles

·         Indoor or outdoor cultivation

The plant care, as well as their watering needs, will vary when it comes to deciding if you will be growing them indoors or outdoors. Hence, the grow bag size will vary about indoor or outdoor cultivation.

·         Temperature

Tomato is a warm-loving crop, so you need to meet the temperature requirements for this plant. However, too hot a climate or scorching sun can burn the tomato plant and cause splitting. But tomatoes can be grown all year round within a greenhouse. A bigger grow bag is ideal for your tomato if the temperature in your region is always hot or too cold.

·         Watering needs – What size grow bag for tomatoes

The tomato plant requires adequate water. However, the plant should not be too soggy. If you’re using a small grow bag for your tomatoes, it usually requires you to water more. For instance, grow bags that are smaller than 8 inches may require you to water twice or even more every day.

So, try to choose the ideal grow bag that is suitable for your tomato variety if you don’t want to go through the stress of watering at regular intervals.

·         Portability of grow bag

How frequently you will need to move your grow bag is also an important point to consider when choosing the ideal-sized grow bag.

·         Location

You should also consider the location of your area to determine the size of grow bag to be used for your tomato plant.

Consider things such as different seasons and hot temperatures during summer to prevent the root of your tomato plant from baking. Then, also consider the susceptibility of root rot during the rainy season in your region.

Portability Of Grow Bag For Tomato

What Size Grow Bag for Tomatoes of Determinate and Indeterminate?

  • Determinate tomatoes

Determinate tomatoes are smaller varieties that can grow up to 5 feet tall, and they can thrive in a small grow bag.

So, for determinate tomatoes, it is usually recommended to use a 20-gallon or bigger grow bag. Then the grow bag should be at least 10 inches in diameter and have a depth of at least 8 inches.

  • Indeterminate tomatoes

Most indeterminate tomato varieties can fit 20-gallon size grow bags or larger. Then the grow bag for an indeterminate tomato variety should be at least 15 inches in diameter and 12 inches deep.

In all these tips for choosing the best grow bag for tomatoes, just keep in mind that the bigger the grow bag, the better for your tomato plant, no matter the variety that has been planted.

5-Gallon Grow Bag Dimensions

The 5-gallon grow bag dimensions are between 12 and 14 inches in diameter and approximately 10 or 12 inches in height. These bags are quite popular amongst gardeners, with the 5-gallon size being amongst the most demanded. The reason for this is that these handy bags can be used to grow a variety of plants which include vegetables, herbs, and flowering plants.

They are often composed of strong materials like polypropylene and other materials. Aside from using these bags to grow shallow-rooted plants, the 5-gallon grow bags also work perfectly when it comes to plants that have deeper roots. These include tomatoes and pepper plants, amongst others.

However, these bags are most effective in growing shallow-rooted plants like spinach, lettuce, and other herbs. If you have little room to grow plants, the 5-gallon grow bag would be an ideal choice. Due to their manageable size, these portable bags are also easy to maneuver. 

Best Soil for Tomatoes in Grow Bags

Ever wondered what is the best soil for tomatoes in grow bags? Well, if you had to ask most growers, they will tell you that sandy loam is the ideal soil for growing tomatoes. This soil consists of three essential components that include sand, silt, and clay, which make up the organic potting mix needed to grow tomatoes. 

Keep in mind that with their ease of cultivation and ability to produce abundant yields, growing tomatoes in the right environment is highly recommended if you want favorable results. You may be surprised to know that tomatoes are amongst the most common crop that is grown in grow bags.

You may ask, what size grow bag for tomatoes is ideal? Most gardeners opt for the 5-gallon grow bag when it comes to growing tomatoes. But, the most important factor to acquire favorable yields would be to make use of soil that has excellent drainage properties and is rich in nutrients. Keep in mind that the growing medium plays a huge part in the size and taste of the tomatoes as well as the amount they will produce.

Here are a few tips about soil and grow bags that will help you understand a bit better:

  1. Potting soil – This soil type is often used in grow bags because it can be easily acquired from your local nursery or garden center. However, it is advisable to choose potting soil that is specially made for growing tomatoes or other vegetables. The potting soil mix should contain perlite and vermiculite, which will enhance drainage capabilities.
  2. Coco coir – This is an environmentally friendly option that can be substituted for peat moss. Incorporating coco coir into the soil mixture would prove very beneficial when it comes to growing tomatoes. The reason for this is that it is durable, lightweight, and has exceptional moisture retention capabilities.
  3. Compost – To give tomato plants a nutrient-rich environment, combining compost with the existing soil mix would prove beneficial. Thoroughly decomposed compost would be the ideal choice in this instance.
  4. Vermiculite or perlite – Adding either one of these products will aid in promoting drainage and reducing the compaction of your soil mix.

What Size Grow Bag For Tomatoes Of Determinate And Indeterminate

How to Support Tomatoes in Grow Bags?

A lot of growers want to know how to support tomatoes in grow bags. There are actually several ways that you can do this. We understand that grow bags are a common choice amongst gardeners, especially because of limited space issues and flexibility. However, to prevent them from toppling over, tomato plants require support as they grow bigger.  Therefore, we decided to bring the best solutions to you. Listed below are a few support structures that you can opt for.


  • Stakes – are useful for supporting tomato plants. All you need to do is to place the stake close to the tomato plant and connect the stem to it using soft twine or garden tape. As the plant grows, you can adjust the stake and continue to tie the plant to it for support.
  • Tomato cage – The use of a tomato cage is to sustain the plant as it develops. To use it correctly, you should cover the plant with the tomato cage to keep it steady.
  • Trellis – Creating a trellis behind the grow bag is excellent because you can train your tomato plant to climb and grow. Using garden tape or twine to secure the stems to the trellis is advised.

You can be assured that your tomato plants in grow bags will remain upright and yield a plentiful harvest if the advice above is adhered to. 

What Size Grow Bag for Tomatoes? Final Say

Tomatoes can be grown easily in grow bags as well as pots or containers. Just choose the right size for the tomato variety you will be planting.

The ideal grow bag size for tomatoes has been discussed in this post. But you should generally know that the bigger the grow bag size, the better it is, irrespective of the tomato variety.


What is the best size grow bag for tomatoes?

The best size grow bag for tomatoes usually depend on some factors. The major factor that you should first look at is how big or small the tomato variety is.

What size grow bag is needed for tomatoes?

The grow bag size required for tomatoes should be as large as you can find. For instance, a 10 gallon grow bag size is fine for a single tomato plant.

What size fabric grow bag for tomatoes?

The fabrics used by grow bags are usually made of non-woven pressed fabrics and they come with small holes for air circulation and drainage. You can use a 5 or 10 gallon fabric grow bag for a determinate patio tomato variety. Then bigger fabrics grow bags can be used for bigger tomato varieties.

What size grow bag for indeterminate tomatoes?

The ideal size of grow bag to be used for indeterminate tomatoes variety is at least 20 gallons or larger. Also, make sure the grow bag is at least 15 inches in diameter and at least 12 inches deep.

Learn more about Tomato Plants Not Growing – What Could Be The Problem? 5 Problems Related To Tomato Growth

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