Tips For Growing And Harvesting Heirloom Tomatoes In Pots

Harvesting your own fruit and vegetables is one of the most rewarding parts of gardening. Many people opt for tomatoes because they are straightforward to grow, produce a large crop, and are easy to incorporate into a variety of meals. Growing tomatoes in pots is not uncommon and for very good reasons. I’ll explain some of them further below. Here are some tips to help you grow and harvest heirloom tomatoes in pots successfully!

What are Heirloom Tomatoes?

First things first, if you aren’t familiar with the term heirloom I should explain. Heirloom tomatoes defined as are open-pollinated, non-hybrid varieties of tomato (heirloom tomato if you live in the UK). Since they have been grown in various places and under different circumstances they have qualities that can be different than hybrid tomato varieties. They will have a large selection of colors sizes and weight. The typical tomatoes bought in a store are hybrids and the genetic selection is done for the benefit of the commercial farming/packaging/shipping community and not necessarily for the benefit of consumers. you can find them in typical types such as; cherry tomatoes, grape, or beefsteak tomatoes.

Reasons to grow tomatoes in pots

There are a few good reasons to grow tomatoes in containers rather than in raised beds of directly in the ground. A lack of garden space is one very good reason. Many people live in apartments of in homes that just don’t have a lot of space outside and tomatoes need a ton of sun. You can save money by growing your own you can buy vine ripped tomatoes online but they can be expensive. Another very good reason is to be able to control the environment the tomatoes grow in. You can better control the soil quality, weeds, watering, and pests by growing in pots rather than directly in the ground. A raised bed will also work for these purposes but they do take up room, you need to buy wood and assemble it. Over time you also need to till and amend the soil, so as with direct sowing in the ground it does take extra tools and work. Having your plants in pots or hanging baskets take a lot of extra work and tools out of the equation.

heirloom tomato, growing tomatoes

Getting started growing tomatoes in pots

There are some simple and obvious things you will need to get started and will ensure success in growing your container tomatoes.

  • Choose the right size pot. Heirloom tomatoes can grow quite large, so make sure to choose a pot that’s between 16- 23 inches in diameter and has drainage holes. Container pots are usually sized by the gallon, so a 16″ wide container is 10 gallons while a 23″ wide container would be a 25 gallon container more or less.
  • Choose the right tomato variety. There are both determinate varieties and indeterminate varieties. Determinate tomatoes grow to a certain height, produce fruit, then stop. Indeterminate tomatoes grow almost continuously and produce along there stems. Both will need stakes but the indeterminate varieties need more space and stakes that are 5 feet tall or more.
  • Use high quality potting mix. Since heirloom tomatoes are heavy feeders, it’s important to use a potting mix that’s rich in nutrients. Look for potting soil that contains composted manure and/or organic matter.
  • Water regularly. Heirloom tomatoes need consistent moisture, so be sure to water your plants deeply and regularly (about 1-2 inches per week). Mulching with straw or bark chips can help retain moisture in the soil.
  • Slow release fertilizer. Your tomatoes will need to be fertilized every 3 weeks with a balanced fertilizer such as 4-4-4. Down to Earth makes really good organic slow release fertilizer and can be found on Amazon. If you see what looks like bruising on your early tomatoes, you might have blossom end rot. You will need to add calcium to your garden soil.
  • Provide support. Tomato can grow very tall especially indeterminate tomatoes. Larger varieties are also heavy and need some support. It’s important to provide them with support such as cages or stakes. They should be 3 to 5 feet high to ensure they don’t topple over. Be sure to tie the stems loosely so the plant doesn’t get damaged.
  • Pest Control. Heirloom tomatoes are especially susceptible to pests such as aphids, tomato hornworms, and whiteflies. Be sure to check your plants regularly and take action if you see any pests. One product you should always have on hand is neem oil, it is an all natural pesticide that won’t harm your plant or soil.
  • Harvest often. Tomatoes are best when they’re ripe, so be sure to check your plants daily and harvest the fruit as soon as it’s ready. This will also keep away pests and critters as leaving your tomatoes to rot will attract both.

When & how to grow tomatoes

The growing season for tomatoes in going to be in the spring for an early summer harvest for most of the US, except if you live in USDA growing zones 10 or above then you will start growing tomatoes in pots during the fall and harvest during the winter time.

Depending on the length of time the variety of tomato you chose takes to fully mature you can typically sow seeds directly in your potting soil, you should not need to start indoors unless you live in the above 45 degrees longitude.

You’ll not need to concern yourself with spacing as you should only grow one tomato in each of the containers you use. Plant 2-3 seeds in each of 10 or 25 gallon container you use. If only one plant grows great, but if more than one grows pull out the less full slower grower. I always try and transplant the one I pull out. Sometimes they will continue to grow but often they die.

Caring for your tomato plants

In general, growing tomatoes is fairly easy, and it should be possible in many different climates. However, hot or humid weather can make the process a bit more difficult. The two biggest problems you’ll face are excessive heat and blight, which is a disease that affects the growth of your plants. If you live in the South of the USA or another area of the world that is very warm in summer, you’ll have to protect your plants from these dangers.

Excessive Heat 

Average tomato plants that haven’t been bred to withstand very hot temperatures might not do very well in warm climates. They will start to wilt and drop blossoms, or the fruit may not be able to set even if there are enough pollinators around. With most plants, you might encounter this issue if the days are warmer than 90ºF and the night temperatures exceed 75ºF. Your tomatoes will stop producing fruit and simply focus on surviving the heat wave.

To minimize the problem, you will need to make sure that all the other conditions are optimal. Provide your plants with plenty of nitrogen so that they can develop healthy leaves but balance it out with phosphorus and potassium because they might otherwise produce many leaves with very few fruits. If you’ve had trouble with tomato plants in the past, you should opt for varieties that are resistant to the heat.

growing in containers, plant tomatoes


Many areas of the South are not only hot but also humid, which creates ideal conditions for a fungus called blight to infect your plants. There are two different kinds of this disease that can affect your tomatoes’ leaves, stems, and even their fruit. Early blight often occurs in the first half of the tomato-growing season, after heavy rainfall. If you catch it quickly, you can rip off affected leaves, but if the plant is already heavily affected, you might need a fungicide.

If your plants have late blight, the leaves will develop blue-gray spots that turn brown later on. When not treated, it can kill plants very quickly, so you’ll need to act and apply organic fungicides immediately. Copper spray is an organic blight killer that can be found at your local gardening center or online, and you can apply it once a week or after rain.

Preventing Problems 

tomatoes, green, plant

As mentioned, you can buy plants that are resistant to excessive heat and can therefore produce tomatoes even if the temperatures exceed 90ºF. The same goes for blight, as there are certain varieties that won’t be so affected by the disease. Even if they contract it, they will still produce a good crop of tomatoes. Aside from buying the right plant, you can also prevent problems by being careful about not getting the leaves wet.

Always plant your tomatoes at least 24 inches apart so that air can move between the plants. You should also avoid watering them from the top and instead water the soil below them because you don’t get any moisture on the leaves that way, thus preventing the growth of blight. It’s important to remember that blight spores can live for a year, so rotating your crops can ensure that your new plants aren’t affected by the disease from the previous year.

Tips for Harvesting Heirloom Tomatoes from Pots

  • When the tomatoes are ripe, cut them off the vine with a sharp knife.
  • Be sure to leave a couple of inches of stem attached to the fruit.
  • Avoid bruising the tomatoes by handling them gently.
  • Place the harvested tomatoes in a single layer on a tray or cookie sheet and put them in a cool, dark place until you’re ready to use them.

The Best Heirloom Varieties for Southern Climates

best tomato varieties, growing in potting soil

Arkansas Traveler

This tomato plant originates in the Ozark Mountains and has been around for over 100 years. The fruit are medium-sized and mild, and they resist cracking. You should pick them when the fruit start to develop a pink hue, as they will never become as red as hybrid tomatoes. On average, it should take about 75 days for your fruit to be ready. Arkansas Travelers are ideal for hot climates and droughts because they will keep producing fruit, even if the temperatures climb. This heirloom variety is an indeterminate, grow in containers well, with an approximate 5 feet tall in height.

Dad’s Mug

Dad’s mug tomatoes also originate in the USA. They are great for making paste or canning because they have very few seeds and a thick skin. Similar to the Arkansas Traveler, they need to be planted in full sun and in well-drained, slightly acidic soil. While the optimal temperature for this variety is 80 to 85ºF, they should be able to grow in warmer climates, as well. If you’re starting them from seeds, it will take 85 days until fully ready. This variety is an indeterminate tomato that grows 4 to 5 feet tall, and makes great container tomatoes.

San Marzano

san marzano tomato plants

Anyone looking for a very popular and high-yielding tomato? You can’t go wrong with the San Marzano variety. It is great for growing in containers. This historical plant was developed in 18th century Italy, so it has always grown in warmer and more Southern climates. You can either grow these from seed or buy some young plants from your local garden center. They should be readily available in many parts of the US.

San Marzano have a large root system, so you should plant them in big pots or straight into the ground. They need a minimum of 6-8 hours of direct sunlight, and the soil needs to drain well. Within 70-80 days, you will have a large harvest of long and thin tomato fruit that have a strong and sweet taste. San Marzano tomato plants are also indeterminate that can reach 6 to 8 feet tall.


homegrown tomatoes, growing tomatoes in containers

Another very popular variety is Brandywine, which are well-known all around the US for their large size fruits with ridges that make them look like a pumpkin, and the amazing taste. They have been around for many decades, and it is believed that the Amish first brought them to the country. Growing these tomato plants you will need some large stakes

Although they can grow very well in southern climates, Brandywine tomatoes are a bit more care-intensive than some of the other varieties because they take longer to ripen and are therefore more susceptible to disease. If you’re a beginner gardener or have never grown tomatoes before, you might want to choose one of the other types first and then progress to these in later years.


These wonderful fruits are grow tomato fruits in clumps that are bite sized. They will produce early, in only 65 days and grow 6 feet tall. These cherry tomatoes make great plants in pots but do need stakes for support. Make sure to use good potting mix and are on of my favorite tomato to grow. Their growing season will extend into even the hotter months.


We have the Campbell Soup Company to thank for this tomato variety, they developed this medium to large red fruit almost 100 years ago. It was later improved by Rutgers University 15 years later. It’s principle purpose was for canning, hence Campbell’s interest in producing its own tomato. It is a one of the determinate tomatoes that grow 4 – 5 feet tall. It is perfect for container gardens, expect deep red fruit in about 80 days.

You can buy my ebook on growing the perfect tomatoes.

Posted by Amaral Farms

HI and thanks for visiting my blog. I guess I would say I have always been a gardener at heart. My parents gardened and I helped them from a young age. As an adult I took to the organic movement and began gardening using almost exclusively organic methods. My focus has shifted the last decade to add heirloom gardening to the mix. By no means an expert, I do enjoy it and spend at least a few hours a week dedicated to it. I hope you enjoy and gain some value from my blog. Check out my tips for growing tomatoes in pots.