How to Choose the Most Disease Resistant Tomatoes for Your Garden

Tomatoes are very generous plants but they also get sick with an awfully long list of diseases!

In fact, from blight to spotted wilt virus there are 63 different ailments that your tomato plants can catch!

If you want to avoid becoming a nurse to your tomato vines, you have a way out though: disease resistant varieties of tomatoes!

Disease resistant tomatoes are varieties selected and bred over the years to resist some of the most common tomato ailments like Fusarium and nematodes. Each variety is resistant to some, even most, of the common diseases, but not all. For this reason, we have divided the varieties into categories according to the diseases they are resistant to:

  • Fusarium and Verticillum
  • Fusarium, Verticillum and Nematode
  • Fusarium, Verticullum, Nematode and Mosaic Virus
  • Tomato spot and wilted virus
  • Blight

This article will guide you through the problems of tomatoes and disease, and best tomato varieties that have some level of resistance to late blight and other diseases for your area that will grow best where you live.

Why Tomatoes Catch Diseases?

Why Tomatoes Catch Diseases?

Some plants are naturally disease resistant, others, like tomatoes, are not. But the question is why? Think about the tomato vine: where does it come from? What does it look like? How does it grow? The answers to these questions will explain why they are so “disease prone”.

  • Tomatoes do not come from temperate regions, but from South America. Like all plants, when they grow away from their natural habitat they become more vulnerable to diseases.
  • Tomatoes have a very vigorous growth and juicy fruits. When plants grow fast, like tomatoes do, they can be more easily attacked by pathogens, like molds, viruses etc. Then the tomato fruits are super juicy and often have a very thin and delicate peel.
  • Tomatoes like heat and water. Heat and water are perfect environments for pathogens like bacteria and fungi.
  • Tomatoes are grown intensively. Maybe the biggest cause of tomato diseases is the way they are grown. Intensive farming and gardening is a major cause in the weakening of plants and in the degradation of the soil.
  • Tomato varieties have been bred and selected for centuries. When you select a variety, you limit its genetic potential, choosing all plants that are very similar. This makes them less capable to fight off certain diseases…

But… if you risk getting your tomatoes more susceptible to diseases if you select the, for example, for their fruit size, you can also select them for their resistance to diseases…

How Are Disease Resistant Tomatoes Developed?

Disease resistant tomatoes are bred to be such. But what does it mean, in detail? There are basically two ways to go about it: selection and hybridization.

We say selection when we choose to reproduce (seed and grow) tomatoes with a specific quality. Let me give you a practical example.

Imagine you have a filed of San Marzano tomatoes and they catch blight. Most of them get sick, many die…

But you notice that some plants don’t get it!…

What does it mean? It may mean that they have the ability to fight it off in their genes.

So you seed these, and grow them. They catch blight too, but less than before.

You grow the ones that don’t… and so on for a few generations, till you see that your tomatoes just don’t catch blight. You have “isolated” the ones hat are resistant to this disease.

Hybridization is when we mix two varieties of tomatoes. Some varieties can be resistant to some diseases naturally.

If you cross them with a non resistant variety, some of the offspring will have the right genes to be resistant.

You select these, and not the ones that catch it, and you get a new variety which is resistant like one of the parent varieties.

All very scientific, isn’t it? But how about GMOs?

Disease Resistant Varieties and GMOs

GMO technology is not just breeding or hybridization. It means changing the DNA of plants directly, with bits of DNA imported from outside.

There are some GMO tomatoes that are disease resistant, but we will not be presenting them here.

GMOs are a massive ethical and environmental issue and an economic one as well.

We will only give you hybrids and cultivars produced naturally, through the toil and experience of farmers, growers, gardeners and botanists.

But what types of disease can your tomato vines catch?

Types of Tomato Diseases

Types Of Tomato Diseases

We said that there are in all 63 known diseases that can affect your tomatoes. They can affect roots, stem, leaves, flowers or fruits.

Basically there are ailments for each part of your tomato plants. But some are common, others are not. Some are very serious, others are less serious.

Anyway, these disease can be grouped into big categories:

  • Fungal diseases
  • Bacterial diseases
  • Viral diseases
  • Nematodes (these are parasitic round worms).

These are pathogen caused diseases.

There are other smaller categories (like viroids and omyocetes) like these, but we are not writing a scientific study on tomato diseases, are we?

But then there is another group of diseases which has “no resistance” because these are cause by us or other factors, not pathogens:

  • Herbicide diseases
  • Insecticide diseases
  • Nutrient toxicity
  • Nutrient deficiency
  • Weather damage (this includes hail, and, well, also “being struck by lightning” in the official list – who said that botany can’t be fun!)

Ok, you got the point. Disease resistant tomato varieties are resistant to ailments caused by pathogens, not others.

There is no variety that can resist impoverished soil, which is by far the biggest cause if plant disease all over the world.

How to Understand Disease Resistance Codes for Tomatoes

Here cones the easy bit! Tomato diseases have codes! Scientists, growers, and gardeners have made it easy to understand which disease a tomato variety is resistant by inventing some easy codes (a few letters) that you can find at the back of your seed packet.

So, whenever you buy tomato seeds, do check out these codes, and they will tell you if and which diseases the tomato variety you are about to buy is resistant to:

Tomato Disease Resistance Codes
  • A – Antracnose
  • ASC – Alternaria Stem Canker
  • BS – Bacterial Speck
  • BW – Bacterial Wilt
  • CRR – Corky Root Rot
  • EA or AB – Early Blight (Alternaria Blight)
  • F – Fusarium Wilt
  • FF – Fusarium Races 1 and 2
  • FFF – Fusarium Wilt 1, 2, 3.
  • FOR – Fusarium Crown and Root Rot
  • LB – Late Blight
  • LM – Leaf Mold
  • N – Nematodes
  • PM or On – Powdery Mildew
  • ST – Stemphylium Grey Spot Leaf
  • T – Tobacco Mosaic Wilt Virus
  • ToMV or ToMV:0-2 – Tomato Mosaic Virus races 0, 1 and 2,
  • TSWV – Tomato Spotted Wilt Virus
  • TYLCV – Tomato Yellow Leaf Curl Virus
  • V – Verticillum Wilt

How To Read Tomato Disease Resistance Codes And Chart

Just look on the seed packet; if you see one of these codes, it means the variety your are buying is resistant to it. But there is another code you can find, and it tells you “how strong” the variety is against the disease in question:

  • HR – High Resistance, this means that the tomato variety is very strong against the given disease; it is unlikely to catch it and to suffer severely from it.
  • IR – Intermediate Resistance, this means that the tomato variety is stronger than non resistant varieties, but not fully resistant against the given disease. They may still catch it and even suffer, especially in unfavorable conditions or when the disease is strong.

Tomato Diseases in Your Local Area

But which diseases should you look out for to protect your tomato plants and crops? True, you need to know which tomato diseases are typical of your area. There are two ways to go about it.

If you know of any diseases that have or are affecting your local area, make sure you get resistant varieties. You can also check online; there are basically maps of diseases.

For example, anthracnose (code A) is common in the Southern, mid Atlantic and mid Western parts of the USA, while alternaria stem canker (AL) is common all over the USA.

But there is also the climate of your area that tells you which are the more probable diseases. In fact, tomatoes do not get the same diseases and types of diseases in hot and dry regions or in wet areas, for example.

Bacteria Wilt (BW), for example is typical of hot and humid places, while Fusarium crown and root rot attacks plants in cool soil and in greenhouses.

Nematodes (N) too like warm and and humid conditions, while corky root rot affects tomatoes in colder regions, like Canada or the Northern USA.

We almost there now, we are almost about to meet some disease resistant tomatoes, just after a final tip, though.

Non-Pathogen Caused Tomato Diseases and Problems

Signs & Symptoms of Over Watering Tomatoes

We are now giving a quick look at the other diseases, those that don’t come from pathogens, like bacteria and viruses, and how to avoid them.

In tact, there  is no point in choosing disease resistant tomatoes if you then leave them exposed to other health problems.

Let’s start with a healthy environment. The ideal place for a tomato vine has healthy and fertile water, abundant water, hot and well ventilated air.

This last factor is important. The ideal air humidity for tomatoes is between 50 and 70% on average, and it can even higher indoors, but… you need to ventilate it for about 8 hours a day in a greenhouse. Stuffy air is a real problem with tomatoes.

Gardeners know also that tomatoes eat a lot!

They like nutritious soil rich in organic matter. The problem with most soil nowadays is that it is depleted; it needs constant feeding and fertilizing because it cannot retain the nutrients that tomatoes need.

If your soil has been cultivated organically, and especially with permaculture, this would be very good for tomatoes.

Tomatoes also need regular watering; if you notice that the top leaves become limp, it means the tomato vine is thirsty.

Use companion planting with garlic and marigolds to keep pests away from your tomatoes.

make sure you give your tomato plants appropriate spacing

Finally, make sure you give your tomato plants appropriate spacing. Plants that are too near to start with block ventilation; secondly, they can compete with each other, and thus weaken each other. Finally, they can spread infections from plant to plant.

Once you have taken into account all these factors, you can finally choose some disease resistant tomatoes to grow in your garden (greenhouse, in pots etc…).

And we are going to help you with your choice right now!

Our Categories (Groups) of Disease Resistant Tomatoes Explained

Let me explain to you how we came up with these groups. They are not “scientific” groups, but we have put them together according to which disease or group of diseases they are resistant to. This makes the lists we are going to show you very practical.

Fusarium and Verticillum Resistant Tomato Varieties

Fusarium and Verticillum Resistant Tomato Varieties

Fusarium and Vericillum are very common diseases with tomatoes. They are both fungi and they affect most regions of the USA. For this reason, choosing a variety that is resistant to these two pathogens is very wise indeed!

  • Big Daddy Tomato
  • Early Cherry
  • Tomi-T
  • Cedro
  • Easy Sauce
  • Giant Garden
  • Little Napoli F1
  • Patria F1
  • Plum Crimson F1
  • Carolina Gold
  • Jet Star
  • K2 Hybrid
  • Longkeeper
  • Manitoba
  • Medford
  • Mt. Delight
  • Mt Spring F1
  • Pilgrim F1
  • Siletz
  • Supersonic F1
  • Tasty Beef
  • Ultimate Opener
  • Valley Girl F1
  • Tidy Treats
  • Heinz 2653

Fusarium, Verticillum and Nematode Resistant Tomato Varieties

If you live in an area where the soil is moist, your tomatoes also risk nematodes. These are parasites that affect the leaves and the roots of tomatoes. They are common in many areas of the USA and Canada too.

So here are varieties that are resistant to these 3 types of disease.

  • Cherokee Purple
  • HM 4521
  • HM 5253
  • BHN-543
  • BHN-1021 F1
  • Best Boy F1
  • Better Boy F1
  • MiRoma F1
  • Amelia F1
  • Applegate F1
  • Basket Vee
  • Better Bush
  • Impacto F1
  • Sunny Goliath F1
  • Super Fantastic F1

Fusarium, Verticillum, Nematode and Tobacco Mosaic Virus Resistant Tomato Varieties

On top of the three pathogens we have seen so far, there is tobacco mosaic virus which is very common. You can find it all over the world, and it is, as it says on the tin, a virus. But it also has a strange behavior. It spreads by using garden tools after you have used tobacco products. Basically, if you smoke the do a spot of gardening, you may be spreading the virus.

It won’t kill your tomatoes but it will damage the florets and the leaves and reduce the yield of your crop. So, here are varieties that can resist even this strange virus on top of the other common diseases.

  • BHN-968 F1
  • Orange Zinger F1
  • Red Racer F1
  • Caiman F1 (this variety is resistant to a lot of diseases)
  • Corleone F1
  • Grandero F1 (this variety too is resistant to a lot of diseases)
  • Palomo F1
  • Pony Express F1
  • Big Bunch F1
  • Bush Early Girl II F1
  • Celebrity F1 (this variety is resistant to almost all diseases!)
  • Early Girl F1
  • Empire F1
  • Grandeur
  • Pamella

Most Blight Resistant Tomato Varieties

Blight is one of the most common diseases of all plants, not just tomatoes. It too is a fungus and it is typical of warm regions of the USA.

You will recognize it because it forms dark spots on the lower leaves. Then the spits get larger and larger and the leaves drop off.

It will weaken the plants and reduce your crops. In some cases, it can also ruin your tomato fruits though. In fact, in hot regions, the tomatoes may literally crack.

So, here are some blight resistant tomato varieties to grow in your garden.

  • Aosta Valley
  • Brandywine
  • Damsel F1
  • Garden Peach
  • Green Zebra
  • Indigo Blue Beauty
  • Legend
  • Marnero F1
  • Roma
  • Rose de Berne
  • Indigo Rose
  • Juliet F1
  • Plum Regal F1
  • Verona F1
  • Abigail
  • Bigdena (this variety is resistant to a lot of other diseases too, including Fusarium, Verticillum and Tobacco Mosaic Virus).
  • Defiant F1
  • Galahad F1 (this variety is also resistant to Fusarium and Verticillum).
  • Iron Lady F1
  • Medusa F1
  • Mountain Gem
  • Mt Merit F1
  • Old Brooks
  • Rugged Boy F1 (this variety is also resistant to Fusarium, Verticillum, Nematodes and Tobacco Mosaic Virus).
  • Stellar F1

Healthy Tomatoes

Now you know a lot about tomato diseases. You know how they get them. You know which ones are more common.

You know how to read the signs on seed packets that tell you which diseases the tomatoes are resistant to.

You also have a very long list of tomatoes resistant to common diseases and how to avoid problems that don’t come from pathogens.

And I hope this will soon translate into healthy tomatoes in your garden and bigger, but also tastier crops for you, your family and your friends!

Updated on by Amber Noyes

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.