Tomato Fruit Cracking: Why It Happens and How to Fix It

I walked out to the garden one July morning and found half my Cherokee Purple had basically exploded overnight. Not dramatically, just that horrible ring of cracks around the top of each fruit, some of them so deep the tomato had already started to weep. It looked like the tomatoes were trying to tell me something. They were.

Tomato fruit cracking is almost always a watering problem, which is both frustrating and kind of a relief. Frustrating because you caused it. Relief because you can fix it without buying anything.

What Actually Causes Tomato Splitting

Here’s the short version: the tomato skin grew at one pace, and then the inside of the fruit suddenly had way more water than it knew what to do with. The skin loses. You get cracks.

This almost always happens after a dry spell followed by a big drink, either a rainstorm or you finally getting around to watering after a few missed days. The fruit swells faster than the skin can stretch. Sometimes you’ll see radial cracks running top to bottom like longitude lines, and sometimes concentric ones, rings around the shoulders. Both mean the same thing: inconsistent moisture.

In July, this is an especially easy trap to fall into. You get a week of sun, the soil dries out faster than you expected, and then you overcompensate with a long soak. I’ve done this more times than I’d like to admit. Actually I’d like to admit zero times, but here we are.

How to Prevent Tomato Fruit Cracking Going Forward

The fix is boring but real: consistent, deep watering. Not a little every day, not a flood twice a week. You want the soil to stay evenly moist a few inches down, which means watering deeply and then letting the top inch dry out before going again. I wrote more about this approach in my post on deep watering your garden if you want the full breakdown.

Mulch is your other best friend here. A 2-3 inch layer of straw or wood chips around the base of each plant slows evaporation dramatically, which means the soil doesn’t swing from wet to bone dry between your waterings. If you haven’t mulched your tomatoes yet, do it today. This is the most important thing I’m going to say in this article and I’m burying it in paragraph six. Sorry.

I’ve had decent luck using old cardboard under the straw too. Adds a little weed suppression and keeps things even moister down below. Free if you have boxes. Which, come on, everyone has boxes.

Varieties That Resist Cracking

Some tomatoes are just better at handling the boom-and-bust watering cycle. Not immune, but more forgiving. If you’re shopping for next season, or still have time to squeeze in a late start, look for varieties specifically noted for crack resistance.

Juliet is a good one, a roma-grape hybrid that’s almost annoyingly hard to crack. Mountain Fresh Plus was bred partly for this. Jet Star has been around forever and holds up well. On the cherry end, Sungold can crack if you’re not careful, but most small cherry varieties are more forgiving than big slicers just because the skins have less surface area to fail.

Big heirloom types like Brandywine or Cherokee Purple? Beautiful tomatoes, genuinely worth growing, also basically volunteering to show tomato fruit cracking if you look at them funny. Thin skin is kind of their whole thing. You just have to stay on top of watering more consistently. Or grow them anyway and accept some losses, which is what I do. Growth mindset. (Gardening pun. Not sorry.)

What to Do With the Cracked Tomatoes You Already Have

Here’s where I’ll save you some sadness. A tomato with a fresh crack is still totally edible. The clock is just ticking faster because bugs and mold will find that opening quickly. Pick cracked tomatoes the same day you spot them, cut away any soft or discolored parts, and use what’s left.

They’re perfect for sauce. Doesn’t matter what they look like once they’re in the pot. I also just slice them up for sandwiches and salads that day, which is a good excuse to eat a tomato for lunch. Not that I need an excuse.

If a crack has been open long enough to start looking brown and mushy around the edges, compost that one. No shame. The plant already grew you a tomato, it just didn’t quite stick the landing.

For more July tomato problems that aren’t your fault (and a few that are), check out my roundup of common midsummer tomato issues and cheap fixes. Tomato fruit cracking is usually the most demoralizing one because you’re so close to a good tomato. But you can minimize it. Mulch, consistent water, pick fast when it happens. That’s really the whole article.

You’re going to have a split tomato eventually no matter what. The goal is just to keep it from being half your harvest. And honestly, a cracked tomato eaten over the sink in July is still a pretty good tomato.

Photo by Rebecca O’Bern on Unsplash