What Are Heirloom Tomatoes? The Hybrid vs. Heirloom Guide

The hybrid vs. heirloom question is one that could be asked for almost all food crops, but the tomato is the fruit that most often comes up in conversations whenever discussing this topic.

Whether you're here to better understand the difference between the two kinds or if you're here to decide which kind of tomatoes to plant, you're going to find your answer. Specifically, we're going to be covering the following topics. Feel free to jump to an area of interest.

• What Are Heirloom Tomatoes
• Categorization of Heirloom Tomatoes
• The Origins of the Term Heirloom Plants
• Things You Should Know About Heirloom Tomatoes
• Popular Heirloom Varieties You Could Grow
• Collecting Heirloom Tomato Seeds
• The Importance of Heirloom Tomatoes
• What Are Hybrid Tomatoes
• Understand the Science: Hybrid and Heirlooms
• What Kind of Tomatoes Should I Plant

Heirloom vs. Hybrid vs. GMO in 2.5 Minutes

What Are Heirloom Tomatoes?

In layman's terms, the word heirloom stands for something that has been passed on from generation to generation. This is how the Cambridge Dictionary defines the word heirloom.

A valuable object that has been given by an older member of a family to a younger member of the same family, esp. one given several times in this way.

When it comes to the classification of tomatoes, heirloom tomatoes are not a variety on their own, instead, it is a term that encompasses all those varieties that have been passed down from generation to generation by farmers through the years. Heirloom tomato seeds from a season are dried up, saved and planted the following season, year after year.

If you're wondering how many generations or years these seeds must be passed on for them to be classified as an heirloom, I've got the answer. This question isn't answered with a specific number of years or generations, rather, it is defined by a period in time prior to the mass manipulation of food crops for economic purposes.

Most farming experts have decided to call any variety that has not been intentionally cross-pollinated and manipulated for specific traits since before the beginning of the second world war as heirloom tomatoes.

Over the past few years, the commercial domain has been trying to take advantage of the lack of complete understanding of what makes an heirloom tomato, therefore a few experts such as Craig LeHoullier who deal with heirloom plants have come up with a classification.

Categorization of Heirloom Tomatoes

1. Family Heirlooms: These are varieties whose seeds have been passed down from generation to generation and are typically very well suited for local growing conditions.
2. Commercial Heirlooms: These are open-pollinated varieties that are in existence since before 1940.
3. Mystery Heirlooms: This is the way most of the different heirloom varieties originated. Mystery heirlooms are those varieties that are a result of natural cross-pollination among tomato varieties that are already classified as an heirloom.
4. Created Heirlooms: These are heirloom varieties that are a deliberate crossbreed among two heirlooms or an heirloom and a hybrid. The reason to do this is to de-hybridize an existing hybrid or to grow heirlooms with certain characteristics. These varieties are the closest cousins of the commercial hybrid tomatoes in my opinion.

The Origins of the Term Heirloom Plants

Jesse Raymond Hepler, the father of Bill Hepler, "America's Youngest Seed Grower" from the Billy Hepler Seed Company was the first to associate the term heirloom with plants. There's an interesting history behind the origin of this term, a brief account follows:

Kent Whealy, one of the co-founders of the Seed Savers Exchange, a non-profit organization that preserves heirloom plant varieties and is among the largest non-governmental seed banks in the United States in the 1997 "Harvest Edition" wrote about the origins of the word Heirloom. Whealy stated that he remembered seeing this word applied to plants on the cover of one of John Withee's issues of Wanigan Associates and had asked John for permission to use the term. That's when John admitted that he stole the term from a certain J.R. Hepler. Bill Hepler later wrote to the seed savers exchange with a story of his company, his father and the use of the word "heirloom" with respect to plants.

He started using the term heirloom varieties with respect to the beans in the late 30's because these varieties were indeed family treasures.

— Bill Hepler

J.R. Hepler loved collecting a variety of beans, especially varieties that were passed down through a family for generations. His family had some of their own seeds that were hand-me-downs.

This is how he defined the term heirloom beans: "We call those beans which have been grown for many years in one neighborhood, but which have never found their way into commerce, Heirloom Beans. The letters that we received from the people who sent in the beans were very interesting. There are records of beans having been in a family anywhere from 75 to 150 years."

His son Bill thinks that he used the word heirloom for these beans because they were indeed family treasures being passed down, a sort of family heritage. This is in line with the definition of the word heirloom. This is the interesting story of the origin of the word heirloom plants. I hope you enjoyed learning about it, as much as I did.

Things You Should Know About Heirloom Tomatoes

There are quite a few features of heirloom tomatoes that are quite different from their hybrid counterparts. Let's take a few of the most important things that you should know:

They Come in All Sorts of Shapes, Sizes, and Colors

Unlike the typical roundish, red tomatoes that we see sold in supermarkets, heirloom tomatoes come in a variety of shapes and colors. Some of them are green even when ripe and ready to eat. You would also find a lot of yellow, purple and maroon tomatoes. They are also almost always not completely smooth and they tend to have bruises, something that would never make it to the modern supermarket shelf.

In general, they yellow varieties are milder than the reds, while the greens have a slight zesty flavor. The dark varieties have more savory qualities than sweet.

Heirloom Tomatoes Are Delicious

Many people claim that heirloom tomatoes are delicious and hybrids taste like cardboard. This is true to an extent, but not completely. Every variety of tomato has a different flavor and people of different tastes appreciate the different kinds. Hybrid tomatoes can be delicious too. What most people mean to say is that the modern supermarket tomatoes taste like cardboard when compared to heirlooms. This is because supermarket tomatoes are usually picked before they ripen so that they can be transported. Sometimes the fruit is also forced ripe using chemicals.

All fruit only sweetens when it is mature as this is the signal for animals to eat them and spread their seeds. Heirlooms that are not allowed to ripen on the plant would taste pretty much like supermarket tomatoes.

They Are Not Easy to Transport and Cutting Them Requires a Sharp Knife

Hybrid tomatoes that you find in stores have been bred for transport and therefore have thick skins. Heirloom tomatoes, on the other hand, are very delicate and have thin skin and are instead bred for flavor and color. Due to the thin skin and the delicate nature of the fruit, you're going to need a very sharp knife to effectively slice heirloom tomatoes, anything else would result in a mushy pulp. Sharp serrated knives are usually a good option.

They Are Not Always Organic

There is a false notion out there that heirloom equals organic. This is not true. Organic refers to plants grown without the use of chemical fertilizers and it has nothing to do with the variety of tomato plant. Heirloom tomatoes can be organic, but they don't have to be.

Popular Heirloom Varieties You Could Grow

To help you get an idea of the different varieties of heirloom tomatoes that you could grow, let's take a quick look at some of the most popular and delicious choices:

1. Yellow Pear Heirloom Cherry Tomatoes

This is a mild flavored tiny tomato that grows in clusters. These are a perfect choice if you're looking to grow something that makes a light snack or if you want a tomato plant that adds to the beauty of your garden. These vines grow to heights of 8 feet or higher on average and are therefore going to need adequate support and a stable foundation once you transplant your tomato plants into the garden. The fruit matures within 78 days and requires full sun. Fruit is produced continuously during the summer months.

2. Sun Gold Cherry Tomatoes

A favorite choice among home gardeners, the sun gold cherry tomato is a sweet-tart flavor tomato. The ripe fruit has a beautiful golden orange color. These are the perfect choice for salads and quick snacks while you work in the garden. The flavor develops early and you, therefore, can eat them up to a week before complete maturity. They yield early with approximately 57 days to maturity and they bear fruit throughout the growing season. Also an indeterminate variety, it can grow very high.

3. Brandywine Tomatoes

The Brandywine tomato is one of the few heirloom tomatoes that help spread the craze for heirloom tomatoes to the general public. When grown well, some say that there is no tomato as sweet and rich in flavor. It's an indeterminate variety and grows even after it's begun to produce fruit with each fruit reaching up to 2 pounds (900 grams) each and therefore the plant could use extra support. The time to maturity is longer than many other varieties at 85 days.

4. Black Krim Tomatoes

These are beefsteak tomatoes with a rich, sweet flavor. The fruit is usually violet-brown and purple-red and gets darker on exposure to the sun. When they get sufficient sunlight, they become so dark, they almost seem black. The days to maturity are between 70 - 90 days. It's an indeterminate plant that bears fruit throughout the growing season.

5. Cherokee Purple Tomatoes

The perfect tomato for salads and sandwiches, the Cherokee tomato consistently ranks high on taste tests. The fruit has a purple-pinkish hue with a deep red interior. The vines grow tall and can reach up to 6 feet high and definitely need the support of stakes or cages. The days to maturity are anywhere between 80 to 90 days. If you were to ask your grandparents what a tomato tasted like, they're most likely to describe one of these.

There are plenty of other heirloom varieties that you could try growing. The list above includes some of the most famous out there and they are definitely the varieties that gardeners new to heirloom tomatoes, but not new to gardening would appreciate. More importantly, I did not want to overwhelm you with a huge list of possibilities. It's hard to pick when you've got too many options. If you're looking for more options you could always search for other varieties.

Collecting Heirloom Tomato Seeds

If you love the heirloom tomatoes your garden just produced, it would be wise to store the seeds so that you could grow the same plant the next season. If you look at the different ways people do it, there's one thing in common: the protective slimy coating around the seeds must be fermented away before you can dry and store your seeds. For the best practice, follow the steps below, but before that let's take a look at important points to keep in mind:

• Work with one variety at a time so that you do not get your seeds all mixed up.
• The seed savers exchange suggests that you should avoid the first fruit from the large-fruit varieties, this is probably a way to counter cross-pollination as the first flowers across different varieties could be few and far between increasing the chances of cross-pollination than self-pollination.
• Sometimes when making sauces there is a lot of tomato flesh that gets thrown away, so this would be a good time to harvest some seeds.

Steps for Harvesting Heirloom Tomato Seeds

1. Cut the tomato in half, not along the stalk, but in the other plane so that you can effectively squeeze out the pulp into a wide-mouth container.
2. Cover the jar with a cloth or paper toweling and seal using an elastic band to prevent insects from getting in.
3. Allow the pulp around the seeds to ferment for around 4 - 5 days at around 60 - 65 F (15 - 18 degrees Celcius). Try to keep it lower than 70 F (21 degrees Celcius). But this ideal condition could be tricky in summer, so just keep it in a spot away from direct sunlight, the basement, attic or garage are ideal locations. You want to keep it away from everyday living spaces as it could stink a bit.
4. Shake the container every day and after around 5 days scoop up the top layer of froth and any floating seeds. Dead seeds tend to float, so this is a great way to make sure that you don't have any useless seeds in your collection.
5. You would now see that your seeds have collected at the bottom and the container contains mostly liquid and not thick pulp. Pour this solution through a strainer so that the seeds are separated. Let it stay a while so that the excess water flows away.
6. Transfer the separated seeds onto a paper towel so that they completely dry up. Only air dry the seeds, do not put them in a microwave or oven! Yes, some beginners tend to do this. After around two to three weeks when you're sure that the seeds are dry, transfer them to a bottle or packet and label it.

For a slightly different process, check out the video below:

The Importance of Heirloom Tomatoes

Compared to the early and mid-1900's the number of registered heirloom varieties has drastically reduced as small family farms have disappeared and commercial production of hybrid varieties has increased.

With the loss of heirloom varieties, we are not just losing out on delicious fruit, but also vital genetic material that has evolved over the past centuries, i.e. since the cultivation of tomatoes and its spread across the globe.

Every heirloom variety has evolved in its own way and has developed to survive certain environmental conditions, pathogens, pest attacks, etc. The commercial hybrid tomatoes are engineered to be resistant to certain diseases, but a new pathogen or pest could easily wipe out certain hybrid varieties around the globe.

It is therefore important that the global production doesn't depend on just a handful of hybrid tomato varieties, but a large number of genetically varied heirloom tomato plants.

Jack Harlan, the world-renowned botanist, agronomist, plant collector, and campaigner for crop plant biodiversity conservation had this to say about the loss of heirloom varieties:

These resources stand between us and catastrophic starvation on a scale we cannot imagine. In a very real sense, the future of the human race rides on these materials. The line between abundance and disaster is becoming thinner and thinner and the public is unaware and unconcerned.

— Jack Harlan, retired professor of plant genetics

What Are Hybrid Tomatoes

As explained further down, in the section Understand the Science: Hybrid & Heirlooms, every tomato that you've eaten is scientifically a hybrid. But when it comes to gardening and planting tomatoes from seeds, we have a different definition of hybrid tomatoes.

Hybrid tomatoes are grown from hybrid tomato seeds which are seeds from fruit that was cross-pollinated between two different varieties. In this case, there is no attempt made to develop a seed line such that the seeds from the seed you plant produces fruit just like its parent.

For the collection of hybrid tomato seeds, the natural process of open-pollination which occurs with heirlooms is overridden by manual pollination where the pollen from one variety is used to fertilize the flowers of another variety. This means that the parents of the hybrid seed are two very different tomato plants and the genetic markup of the seed contains traits from both the parents.

Hybrids are usually a mix of varieties to provide some sort of optimum mix of the following traits: maturity time, yield, flavor, disease resistance, skin thickness, required care, plant size, etc.

The sections that follow in this article cover more of the science behind all of this. But before jumping there, let's take a look at what supermarket tomatoes are. We know that they are hybrids, but what kind of hybrids are they?

Supermarket Hybrid Tomatoes: What Are They?

Commercially grown tomatoes are usually F1 hybrids. F1 hybrids are plants that are grown from seeds of a tomato that is the result of the cross-pollination of two stable inbred varieties. This is just as described above.

As a home gardener, you can find seed stores selling hybrid seeds. These seeds grow up to produce F1 hybrids. This does not mean they are supermarket tomatoes. There are many kinds of hybrids, just as there are many kinds of heirlooms.

F1 hybrids are predictable and it is completely understood what the offspring of two different varieties would result in. If the parents are X and Y and the offspring is Z, Z is the F1 generation. However, if you grow Z and let it produce seed, the offspring of Z would not be the same as Z. Some of the seeds would be infertile, most would strongly bear characteristics of X and Y, a few would be the same as the parent, Z. You could choose to continue this line (F2 generation) such that over many generations you get a new stable and predictable Z type of plant where all the seeds produce identical and predictable plants.

Understand the Science: Hybrid and Heirlooms

First of all, it must be pointed out that all tomato varieties belong to the same species, i.e. Solanum lycopersicum (see the table below, source: Letstalkscience).

Any variety other than the wild-type present in Central and South America has been bred by carefully selecting the plants whose seeds would be allowed to grow. In addition to this, the pollination of flowers is controlled among plants with slightly different qualities over many generations.

Therefore, even heirloom tomatoes are technically hybrid tomatoes. The difference between what we today term heirloom and today's hybrids is the fact that heirloom tomatoes have been selected for generations and therefore their seeds produce the same kind of fruit as the parent (as discussed earlier with the tomatoes I called Z tomatoes). This happens because through the generations seeds of any plant that did not match the requirements were not collected and therefore not sowed the following season.

The corollary to this is: Seeds from most of the tomatoes we classify as hybrids (regular supermarket tomatoes) will not produce tomatoes like the parent tomato. A few would, but most won't. If you're interested in the science of this and want to learn more about it, you should look up Mendel's experiments. I have linked to an explanation that explains this in an easy to understand way with images.

If you're still not sure what this all means we could try a different approach. Just like tomatoes, all dogs are the same species. Two Dalmatian dogs have Dalmatian pups (heirloom today, but in the past, there was a lot of breeding that today resulted in the Dalmatian) but a Labrador retriever and the standard, Moyen, or Miniature poodle gives rise to the Labradoodle (hybrid). Now add in the fact that tomato plants can pollinate themselves (through insects) and you would begin to understand the science behind it.

Before we look into selecting the right kind of tomato for your garden, let's give this one last try with a short video explaining Mendel's experiments and the way basic genetics works. Understanding this may help you breed a tomato that you love that is not found anywhere else.

What Kind of Tomatoes Should I Plant

Before you decide what kind of tomato or tomatoes you should grow, you first need to determine what you're going to be doing with them. You should also ask yourself if you plan on collecting seeds from your crop to re-grow in the future.

Different varieties are good for different purposes. I can't cover the individual traits of all kinds of tomatoes here and have already described five popular choices earlier in this article. This guide is therefore only going to be a basic guide between choosing heirloom and hybrid tomatoes.

When you talk to people who grow tomatoes in their vegetable garden for home consumption and to those who grow them for sale in local farmers markets you notice some subtle but important differences.

When growing for home consumption people typically do not store seeds and choose to buy their seeds each year. At the same time, families love to have a variety of fruit and therefore choose to grow both hybrid and a variety of heirloom tomatoes. If you're buying seeds every year you could do this without worry, but if you plan on storing seeds to grow in the future, this could lead to cross-pollination issues. This article is a good guide on preventing cross-pollination when growing different kinds of tomatoes close to each other.

When growing for farmers markets, most people look to lower costs and hence they typically store seeds and don't buy them every year. Most beginners tend to grow just one or two heirloom varieties that are bred for the particular region. Some professionals tend to grow an entire tomato salad to offer a variety. If you grow different kinds, it is advisable that you keep a close eye on cross-pollination as it could negatively affect your business as soon as two seasons in the future.

Growing Hybrid Tomato Seeds That You've Just Bought

• The fruit from all the seeds would be similar to what was advertised on the seed pack.
• Seeds collected from these tomatoes will mostly produce plants with features of the parent plants that constitute the hybrid and therefore second generation fruit would mostly be a surprise.

What to Expect When Planting Heirloom Tomato Seeds

• Buy seeds once and you don't have to ever again.
• Easily collect seeds and plant again the next season and the tomatoes would be just like the parent tomato provided there was no cross-pollination.

If you've decided what kind of tomato seeds you'd like to grow this season, you may be interested in my article on how to grow tomato seeds. I do not want to repeat myself here as the process of growing and caring for the tomato plants is essentially the same whether they are hybrid or heirloom because they are all the same species.

If you love gardening and you have two or more varieties of tomatoes that you love, say the size of one and the flavor of another you could try hand pollinating to get your own hybrid seeds. This can be a really interesting hobby, but patience is key. Since you begin with a small gene pool these plants may not end up being the best survivors against different kinds of diseases, etc. So, treat it as a pet project and nothing more when done on a small scale.

Brandon Lobo (author) on April 14, 2019:

Hi Edward. Good luck!

Edward on April 14, 2019:

This is great. Trying my hands on Cobra hybrid tomatoes in Port Harcourt, Rivers State, Nigeria. I hope to be the biggest tomatoes farmer in Africa and reading materials like this tells me it's possible. Thank you for this great work

Larry Conners from Northern Arizona on January 27, 2019:

Very interesting and well organized hub...always wanted to grow heirloom tomatoes...Thank you for this..

I live in Texas now, near Dallas...Is the climate and soil such that I could raise heirloom tomatoes...? Is there a planting guide for the US...?