Weird-Looking Tomatoes? Why Catfacing Happens and What To Do About It

Anyone who’s grown tomatoes knows it’s rare that we get a crop of perfectly smooth and round fruit in summer. Sometimes they’re bumpy, or lumpy, or so deformed or covered in scars that they become freakish looking. These “Franken-tomatoes” aren’t caused by pests or diseases—they’re the result of a common condition called catfacing. And yes, you can do something about it.

Linda Ly
Weird-looking tomatoes? Why catfacing happens and what to do about it

Every summer, I’m bound to find a wonky tomato or two on my plants—and I don’t think I’m alone in this. Rarely do we get a bumper crop of sweet, juicy fruit without a single blemish in sight, right?

But sometimes I’ll come across a tomato that’s so weird and freakish looking, I start to wonder if I should even eat that thing.

What I’ve got here is a catfaced tomato.

Close-up of an immature green tomato on a vine with severe catfacing

Why it’s called that, I’m not really sure. I don’t quite see the resemblance, but if you’ve been wondering why your tomatoes look all deformed with cracks and scars, I’ve got answers.

First, what is catfacing?

Catfacing is a physiological disorder that causes a tomato to develop severe physical abnormalities on the blossom end of the fruit (opposite the stem). Oftentimes the abnormalities appear as irregular lobes, crevices, or indentations in the fruit, with cracking and cork-like brown scars that look like rings or zippers. (Don’t confuse catfacing with naturally ribbed tomatoes, by the way.)

The damage may extend deep into the flesh, causing a misshapen tomato, or it may form near the surface, with the only sign of catfacing being a scar on the bottom of the fruit.

A ripe orange tomato with green stripes on a white plate, with minor catfacing on the bottom of the fruit
This tomato looks “normal” until you turn it over and see the catface scarring on the blossom end

If you see cracks in the skin, it isn’t always catfacing, by the way. Cracks and splits in tomatoes can also result from heavy rain or excessive watering.

Common causes (and what you can do)

Catfacing is actually a pretty common problem, but so far it hasn’t been fully understood. However, it’s common enough that scientists have developed a few theories as to what causes it.

Is there anything you can do about it? Yes… and no.

Heirloom varieties and large fruits

Malformations are most prevalent in heirloom tomatoes and large-fruiting varieties, so the first (and also the easiest and least expensive) way to prevent catfacing is to grow tomatoes that are less susceptible to it.

Large green tomato on a vine with deep crevices and brown scars in the fruit caused by catfacing
A large round heirloom tomato with severe catfacing

The larger and rounder the fruit, the greater the chance of catface. So, avoid those big beefsteak heirlooms, and stick with smaller tomatoes (such as cherry, grape, plum, or icicle types) or hybrid varieties that typically aren’t affected.

Cool nighttime temperatures

It’s generally believed that catfacing occurs when there’s damage to a developing tomato blossom. This happens if there’s a string of cool nighttime temperatures (below 55°F), which result in improper or incomplete pollination of the blossom. When the flower is stressed right after it’s pollinated, the tomato ends up puckering and bulging as it tries to grow around the damaged flower.

You see this more often in early summer (or in fall) when temperatures tend to drop off in the evening. Luckily, it goes away as the weather warms up, so you’ll only get catfaced tomatoes with the first flush of fruit.

Using tomato teepees or “walls o’ water” (which you can see in action in my post about growing tomatoes in pots) can help with those cooler evenings early in the season, but only works with younger (smaller) plants.

In my garden, I keep an eye on weather all season and am prepared to cover my plants with frost cloth if it looks like nighttime temps will dip dangerously low.

I’ve also found from experience that growing tomato varieties that are tolerant of cold helps offset pollination problems that might occur. These varieties include Oregon Spring, San Francisco Fog, Siberia, Glacier, Northern Lights, and other similarly-named tomatoes that were bred for cooler climates.

As for those chilly autumn nights, you can try an early-maturing tomato variety that will ripen before things start to cool off late in the season. (Look for tomatoes that mature in 80 days or less, not those that take 100 days.)

Disclosure: If you shop from my article or make a purchase through one of my links, I may receive commissions on some of the products I recommend.

Big swings in temperature

Catfacing also seems to happen if there’s an extreme fluctuation in temperatures between day and night. I see this in my Central Oregon garden, where I grow big heirloom tomatoes in weather that can go from 85°F in the middle of the day to 50°F at night (even in summer). Yikes, that’s two strikes against me.

One way to temper the effects of weather is to grow a short-season tomato variety that will flower and fruit before the hottest days of summer arrive. You can also hang a shade cloth over your plants to offer some midday relief (which may also help with blossom drop—see my recommendation in the box above). Other than that, there’s not much you can do about those hot days.

Heavy pruning

Heavy pruning of indeterminate tomatoes may also cause catfacing, as it reduces the amount of auxins in the plant (auxins are natural hormones that regulate growth). This isn’t definitive—just a theory.

If you regularly prune your tomatoes back to just the main stem and notice a lot of catfaced tomatoes, it may be worth letting a few plants grow freely to see if that solves your problem. I like using a Florida weave trellis to help rein in all the vines.

Thrip damage

It’s sometimes thought that a thrip infestation may cause catfacing, as these pests damage the pistils of tomato blossoms.

If you see thrips (or any pests) on your tomato plants, be sure to handle it right away so the pests don’t spread to other plants. Remove the damaged foliage and trash it.

Biological controls are my favorite way to get rid of thrips and similar plant-feeding pests, so I aim to grow a variety of flowering annuals and perennials that attract their natural predators (which include green lacewings, minute pirate bugs, and parasitioid wasps). While you wait for those plants to grow in, you can attract the good bugs with this homemade bug chow.

A lot of these flowers are also a favorite of other beneficial insects, like our beloved bees and butterflies, so put them all around your garden: daisies, cosmos, marigolds, sunflowers, sweet alyssum, yarrow, dill, parsley, mint, and many more.

Read more: The best bee-friendly flowers to grow in your garden

Two large red tomatoes on a wooden surface with catfacing on the blossom end of the fruit
They’re ugly, but you can still eat them

To eat or not to eat

In general, a catfaced tomato—while imperfect or downright ugly—is still edible.

Sometimes the bumps and folds may cause the skin to stretch too much and simply break open, leaving an open wound on the fruit. The wound may “crust” over, leaving a brown spot or an area of very thin skin. Any type of wound on a plant can invite bacteria, so in these cases, use your best judgment as to whether the tomato can be eaten.

If it looks like it’s starting to rot, you can often just cut out the soft spot and save the rest of the tomato. If it’s already moldy, compost the whole thing. If it’s cracked, scarred, and weird-looking but otherwise intact and feels solid? Feel free to eat it!

Whenever I get a severely catfaced tomato, I make sure to eat that one first. That way, I can cut it open and find a hidden soft spot before it turns the fruit into a squishy, rotting mess.

2 Comments

  1. Wow! One of my indeterminate heirloom plants gifted me with the biggest tomato ever, and I couldn’t imagine what happened to it as it looked like an amalgamation of many smaller tomatoes mashed into one! Sent a photo last night to my son! It’s ripening fast now that I picked it and we will enjoy it soon! Thank you so much for this information!

  2. Oregon Spring, San Francisco Fog, Siberia, Glacier, Northern Lights, – where can these seeds be purchased?

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