June 15, 2024

The Best Tomato Grow Bag Size for Maximum Yields

So you want to grow tomatoes this year but don’t have the space for a big garden? Don’t worry, you can still get a bumper crop of juicy homegrown tomatoes with the help of grow bags. The secret is choosing the right size bag for your needs. If you go too small, your tomato plants will become pot bound and stunted. Too large and the soil won’t dry out and heat properly, which tomatoes need. For most casual gardeners looking to can a few jars of sauce or make some caprese salad, a 10 to 15 gallon grow bag is ideal. This gives your tomatoes enough room for healthy root growth so they can produce an abundance of ripe fruit, without requiring so much soil and space that it becomes difficult to manage. With the right size grow bag and a little TLC, you’ll be sinking your teeth into a ripe, sun-warmed tomato in no time.

The Best Tomato Grow Bag Size for Maximum Yields
The Best Tomato Grow Bag Size for Maximum Yields

What Are Grow Bags and Why Use Them for Tomatoes?

Grow bags are fabric pots that provide an ideal environment for growing tomatoes. Here are a few reasons to use grow bags:

Excellent Drainage

The porous material of grow bags allows for superior drainage and aeration for tomato roots. Excess water can drain freely, preventing root rot, while still retaining some moisture. The fabric also allows oxygen to reach the roots, promoting healthy growth.


Grow bags can be placed anywhere – on patios, balconies, driveways or in small yards. You can move the bags around to follow the sun during the day. The bags are also easy to store when not in use.

Manageable Size

Grow bags come in a range of sizes to suit the space you have and the yield you want. For a typical patio tomato, a 5 to 10 gallon bag will produce a good harvest. If you have more room, you can opt for 15 to 20 gallon bags for bigger yields. The smaller size also makes the bags easy to move around and lift when full of soil and mature plants.

Healthier Roots

The fabric sides of the bags gently guide the roots in a circular pattern down and outward. This natural root training produces a compact, healthy root ball. The roots stay within the bag and do not spread out under the soil like they do in a garden bed.

In summary, grow bags provide drainage, aeration, portability and natural root training that results in an ideal environment for tomato plants to thrive. With the right care and feeding, you’ll be enjoying the fruits of your labor in no time!

A comprehensive guide in “How to Grow Juicy Tasty Tomatoes“. Your tomatoes will have more flavour and be a lot sweeter than you’ve tasted from any store bought variety!

Factors to Consider When Choosing Grow Bag Size

When choosing a grow bag size for your tomato plants, there are a few important things to consider:


Tomato plants need room for their roots and foliage to grow. For maximum yields, choose a bag that is at least 20 gallons, which will give your plant enough space to produce a good harvest. Anything smaller will stunt the plant’s growth and reduce how much fruit it can produce.

Number of plants

If you want to grow multiple tomato plants in containers, make sure to choose a bag that is large enough for all of the plants. As a general rule, you’ll want at least 10 gallons of soil per tomato plant. So for 3-4 plants, a 30-40 gallon bag is ideal.

Type of tomato

The size of your tomato variety also matters. Beefsteak tomatoes, for example, require more space than cherry tomatoes. For large slicing tomatoes, go with at least a 25-30 gallon bag. Smaller varieties can do well in 20 gallons.


The spot where you place your grow bags also affects the ideal size. Bags in a location with plenty of sun and warmth will need more soil to retain moisture, so choose a larger size. Shadier spots can get by with slightly smaller bags since the soil won’t dry out as quickly.

By considering these factors before purchasing your grow bags, you can choose a size that will give your tomato plants the best chance of thriving and producing an abundant harvest. The effort you put in now will pay off later when you have ripe, homegrown tomatoes to enjoy!

Read more:
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Recommended Tomato Grow Bag Sizes

When it comes to choosing the perfect size grow bag for your tomatoes, bigger isn’t always better. The ideal size depends on the specific variety you want to grow and how many plants you need to accommodate.

5 Gallon

For cherry tomatoes or other compact varieties, a 5-gallon grow bag is a great option. It’s large enough for 1-2 plants but still lightweight and easy to move. The smaller size means the soil will dry out faster, so check moisture levels regularly and water when the top few inches become dry. A 5-gallon bag is also a good starter size if you’re new to container gardening.

10 Gallon

A 10-gallon grow bag is a versatile size that can work for most tomato varieties. It will hold 2-3 plants of slicers, beefsteaks or Romas. The larger volume of soil means moisture is retained better, but you’ll still need to water regularly, especially in hot or dry weather. A 10-gallon bag offers plenty of root space for healthy plants and a good yield of tomatoes.

15-20 Gallon

For maximum yields, especially of larger beefsteak tomatoes, choose a 15-20 gallon grow bag. This size can accommodate 3-4 plants. The added soil helps insulate roots from temperature extremes and reduces moisture fluctuations. However, once filled, these bags can be quite heavy so make sure you place them where they will remain for the season before filling and planting.

In the end, consider how many tomatoes you want to harvest and match that to an appropriately sized grow bag. Pay close attention to moisture and fertilizer needs based on the bag size and your specific tomato varieties. With the right care and feeding, you’ll enjoy a bumper crop of homegrown tomatoes this season, no matter which size you choose!

A comprehensive guide in “How to Grow Juicy Tasty Tomatoes“. Your tomatoes will have more flavour and be a lot sweeter than you’ve tasted from any store bought variety!

Tips for Maximizing Yield in Your Tomato Grow Bags

To get the biggest harvest from your tomato grow bags, follow these tips:

Choose a Large Enough Size

For maximum tomato yields, go with at least a 20-gallon grow bag. Anything smaller will cramp the roots and limit growth. Large bags, around 25 to 30 gallons, give roots more room to spread out and absorb nutrients, which translates into bigger, more abundant tomatoes. Consider the mature size of the tomato variety you’re growing to determine the ideal bag size.

Use Quality Soil and Fertilizer

Fill your grow bags with organic, nutrient-rich potting mix, not regular garden soil. Potting mix is lightweight, holds moisture well and has the right pH for tomatoes. Mix in granular, slow-release fertilizer at planting and follow the directions to determine when to add more during the growing season. Fertilizer provides the nutrients tomatoes need to produce fruit.

Water Regularly

Tomato plants require at least 1 to 2 inches of water per week. Water when the top few inches of soil are dry, and thoroughly soak the entire grow bag. Inconsistent watering leads to blossom end rot and cracked fruit. Never let the soil completely dry out, but avoid overwatering which can cause root rot.

Prune and Stake Stems

Once seedlings are established, prune off side shoots for better air circulation and pinching flowers to focus the plant’s energy on ripening existing tomatoes. Stake the main stems to provide support for heavy fruit. Allow some side shoots to remain for higher yields.

Pollinate Flowers

Gently shake or flick the clusters of yellow flowers a few times a week to pollinate the blossoms. This helps with fruit set when natural pollination is limited. More pollinated flowers mean more tomatoes.

Following these useful tips will help you get the biggest, best tomato harvest from your grow bags. With the right conditions, you’ll be enjoying homegrown tomatoes for months!

Our Top Picks: Best Grow Bag Sizes for Tomatoes

When it comes to choosing a size of grow bag for your tomato plants, bigger is not always better. The ideal size depends on the specific variety of tomato you want to grow and how many plants you need to accommodate. We’ve rounded up some of our top recommendations for getting the best yields from your tomato grow bags.

10-gallon bags

For determinate tomato varieties that only grow 3 to 4 feet tall, a 10-gallon grow bag is a great compact size. It provides enough room for the root system without being oversized. Popular determinate varieties for 10-gallon bags include ‘Celebrity,’ ‘BushSteak,’ and ‘Husky Cherry Red.’ You can fit 2-3 plants in a 10-gallon bag, depending on the variety.

15-gallon bags

For most standard tomato varieties, a 15-gallon grow bag is an ideal size. It suits the needs of indeterminate varieties that can reach up to 6 feet tall, such as ‘Brandywine,’ ‘Cherokee Purple’ and ‘Mortgage Lifter.’ You can plant 1-2 tomato plants in a 15-gallon bag. The extra space will allow for more vigorous root growth to support the larger plant size.

20-gallon bags

If you want to grow extra-large indeterminate tomato varieties or want higher yields, go with a 20-gallon grow bag. Varieties that can utilize the space well include ‘Beefsteak,’ ‘Pineapple’ and ‘Hillbilly.’ You can fit 1-2 plants in a 20-gallon bag. The bigger size means more room for roots and a larger reservoir of soil to hold moisture and nutrients to feed your thirsty tomato plants.

Larger sizes

For very high-yielding varieties or if you want to minimize the number of bags needed, you can use 25-gallon bags or larger. However, it may be more difficult to move and manage bags of this size. It also means a higher volume of potting mix and fertilizer needed to fill the bags. Unless you have experience growing in large containers, we recommend starting with smaller sizes, like 10 to 20 gallons. You can always size up for higher yields once you get the hang of it!

A comprehensive guide in “How to Grow Juicy Tasty Tomatoes“. Your tomatoes will have more flavour and be a lot sweeter than you’ve tasted from any store bought variety!


So there you have it, the best tomato grow bag sizes for maximum yields in your home garden. Don’t be tempted to go too small with your containers, thinking you’re saving space. And don’t go too big either, making your plants work too hard to produce fruit. Stick within the 5 to 15-gallon range for the perfect balance of root space and plant energy. Pay attention to the specific needs of the tomato cultivar you choose as well. Some varieties are more compact while others like to sprawl. The most important thing is to not forget that growing tomatoes should be fun! Keep experimenting with different techniques and you’ll be harvesting basketfuls of juicy homegrown tomatoes before you know it.