"I would say you’re going to get more fruit and better fruit, and your plants will be healthier if you plant fewer plants further apart than if you try to cram in too many.”

 - Marybeth Janerich, Wasatch Community Gardens

Off To A Great Start

You’ve picked out which tomatoes you want to grow, you’ve acclimated them to your garden, and you’ve got them in the ground with good spacing and strong trellising.

Now you just hope your tomato plant is happy, fed, and free of harm for the next few months while it grows award-winning, picture-perfect, delicious tomatoes.

There are lots of opportunities for harm to strike your tomato plant. Your tomato woes can come in the form of a pest, a virus, a fungus, or something as simple as overheating or overwatering.

We cover some common tomato problems below, but if you want to know more, Wasatch Community Garden offers a variety of hands-on tomato courses, including Tomato Planting Tips and Tricks, Tomato Fundamentals, Growing Great Tomatoes, Tomato Pruning and Trellising, and What’s Wrong with My Veggies, which is a two-part class. You can see a complete list of their workshops and sign up for them on their webpage.

Some Common Tomato Problems

Blossom Drop

Cause:

Tomato plants can become stressed if the high daytime temperature is above 85 F, the high nighttime temperature is above 70 F. The pollen can become sterile, and the unpollinated flower will fall off.

Troubleshooting:

Keep a consistent watering schedule. There are a number of smart watering systems that connect to your spigot that you can control with an app.

Try growing some early maturing tomato varieties, such as Early Annie, Glacier, or Oregon Spring in order to increase your chances of getting early fruit set, before the temperatures get so high that you start experiencing blossom drop.

Hamson DX 52-12, a locally adapted tomato!

“This isn’t an automotive part, it’s a tomato variety, and it was developed in Utah by Dr. Alvin Hamson at Utah State University and it’s specifically bred to set fruit at more extreme temperatures than most other varieties of tomatoes,” says Marybeth.

Tomato Cracking

Cause:

This is caused by overwatering. Cracks occur when a tomato’s flesh grows faster than its skin. These tomatoes also tend to be watery and the flavor isn’t as good.

Troubleshooting:

If there’s a big summer storm coming in, you’ll want to interrupt your watering cycle for that day or the next. Again, being present in your garden and knowing your watering cycle is the best answer.

“Tomatoes like moist, well-drained soil,” says WCG’s Green Team Farm Director James Loomis. “They don’t want to be wet and they don’t want to be dry.” James is the tomato expert we interviewed in Part 1 of Growing the Perfect Tomatoes.

Blossom End Rot

Cause:

This is caused by inadequate calcium transport within the tomato plant. In some regions, this may be due to a lack of available calcium in the soil. However, soils along the Wasatch Front tend to have plenty of calcium — so it’s not a lack of available calcium that’s the problem. Soils that tend to be more alkaline inhibit the uptake of calcium by the plant.

You can read more about Blossom End Rot on this Utah State University Extension site.

Troubleshooting:

A consistent watering cycle is the best remedy. Try to avoid overwatering, particularly if your soil tends to be higher in clay.

Blossom end rot is more common in paste and Roma type tomatoes than in other varieties. If you keep seeing this problem, consider growing a different variety. The Pozzano paste tomato is a hybrid that is resistant to Blossom End Rot.

Sunscald

Causes:

Sunscald is caused by your tomato getting baked in the sun. It’s usually because of over-pruning and exposing the fruit to direct sunlight. “You really want to think of that top part of the tomato as a kind of canopy for the fruit beneath,” says James Loomis.

Troubleshooting:

There’s more to pruning than you might think. There’s bottom, top, and sucker pruning. “There are some tomatoes you don’t want to prune and some that you do,” says Marybeth.

Pruning would be a whole new blog post, but if you want to know more about the subject, Wasatch Community Gardens offers a class called Tomato Pruning and Trellising.

Some Common Tomato Diseases

Curly Top Virus

Cause:

This is a virus that is spread by a small insect called a Beet Leafhopper. Once the virus infects a plant, it will die. It often happens early in the season.

Signs that you may have curly top virus: You may notice one of your tomatoes is failing. The leaves curl up and are a purplish color underneath, and you might find the plant is producing premature, small, leathery fruits.

Troubleshooting:

Pull the entire plant up and throw it in the trash, not the compost or the yard waste bin. Sorry guys, this is a fatal one.

Early Blight

Cause:

This is a fungal disease spread by spores that can overwinter in your garden. On the leaves, you will see brown spots like a “bullseye”, sometimes with holes in the center. Early blight usually starts at the bottom of the plant on the older leaves and then moves up the plant.

Troubleshooting:

Proper plant spacing can help prevent early blight, but here’s more from Marybeth:

“If the spores are blown into the garden or are in the soil from last year, spacing plants far apart won’t do much to reduce getting early blight. I’d say bottom pruning can help more, but most importantly, I’d recommend that gardeners practice proper crop rotation; don’t plant tomatoes where tomatoes have been planted for the past three years, especially if you’ve had early blight previously. Gardeners can also look for varieties that are early blight resistant,” recommends Marybeth.

With a bucket of bleach water (recommended disinfecting ratio is ¼ cup of bleach to every gallon of water) and your pruners, cut each affected leaf off and throw it in the trash. After each cut, wipe down your pruning blades with the bleach water. You can also use bleach wipes, you know, the kind that kills 99% of germs.

You can also buy a copper fungicide treatment, which comes as a liquid you spray on the plant. Be sure to follow the instructions on the label.

Regarding early blight, if it’s caught and treated early enough, “it’s like having high cholesterol — it’s manageable and not the end of the world for the plant,” says Marybeth. “It can be fatal if left untreated too long."

Happy Tomato Season!

These are just a few of the most common tomato problems you may run into during the growing season. As mentioned above, if you follow gardening best practices — starting your garden with healthy soil, planting tomato starts with proper spacing, and setting a consistent watering cycle — you will have fewer problems, or better yet none at all!

In addition to the Wasatch Community Gardens’ workshops, you can find further information on tomato pests and problems on the Utah State University Extension site.

Photos used in this blog were provided by Marybeth Janerich, and are part of her tomato curriculum for Wasatch Community Gardens classes.

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