Why do Tomato Split and How to Prevent It

The summer sun beams down as you make your way to the vegetable garden. Vines heavy with ripe, red tomatoes promise sustenance and satisfaction. But as you lift a promising orb to the light, your heart sinks. An ugly crack mars its smooth skin

Sadly, splitting tomatoes is a common frustration for home gardeners. Just when those tomatoes near peak ripeness, errant cracks, and fissures appear, ruining their picture-perfect potential.

While a split tomato is still edible, its shelf life diminishes significantly. And those unsightly cracks make for poor presentation.

Thankfully, there are ways to curtail and prevent split tomatoes. This guide will explore the common causes of tomato cracking and provide actionable tips to help you grow flawless, crack-free tomatoes.

Why Do Tomato Cracks Happen? ( 5 major Culprit)

Several factors can cause tomatoes to split, especially as they ripen. Let’s examine some of the most common culprits behind tomato cracking.

1) Irregular Watering

Inconsistent watering often plays a role in tomato cracking. After a period of drought, gardeners may give their tomato plants a deep, heavy watering. While the thirsty plants appreciate the drink, the tomatoes absorb water faster than their skin can expand. This rapid influx of water causes the tomato skin to split under the pressure.

Conversely, fluctuating between very wet and very dry conditions can also stress tomatoes and lead to cracking. The key is to maintain even soil moisture by watering regularly and deeply, about 1-2 inches per week. Mulching around the plants also helps regulate soil moisture.

2) Hot Temperatures and Rainfall

Hot daytime temperatures followed by heavy rains are another prime scenario for split tomatoes.

As a tomato ripens, heat causes its inner flesh to expand. Then, when heavy rains arrive, the outer skin cannot stretch fast enough to accommodate the swelling of inner tissue. The result? Cracked tomatoes.

Such weather fluctuations are difficult to control. However, paying attention to the forecast can provide a warning to take preventative action (see tips below).

3) Low Calcium Levels

Calcium is essential for tomato skin and cell wall development. Insufficient calcium delivered to developing fruits will cause weak skin that easily splits.

Certain environmental factors can limit calcium availability and uptake in tomatoes. These include:

• Low soil pH – Calcium availability decreases in very acidic soils with a pH below 6.0. Test soil pH yearly and amend with lime if needed to keep the pH around 6.5.
• Drought – Insufficient water prevents calcium from reaching the roots and fruits. Maintain regular watering.
• Over-fertilization – Excess nitrogen fertilizer can inhibit calcium absorption and transport within the plant. Use fertilizer judiciously.
• Root damage – Wounded roots are less efficient at taking up nutrients like calcium. Avoid root damage through cultivation.
• Cold temperatures – Cool weather slows calcium transport. Low night temps below 55°F (13°C) may increase splitting.

4) Excess Nitrogen

Heavy nitrogen fertilization can also aggravate tomato cracking. Too much nitrogen stimulates rapid, lush vegetation growth. This creates highly turgid cells in the tomato fruit that put pressure on the skin, causing ruptures.

Stick to moderate nitrogen levels when fertilizing tomatoes, and avoid heavy doses of quick-release synthetic nitrogen.

5) Varietal Susceptibility

Certain tomato varieties and cultivars are inherently more prone to splitting. Large, thin-skinned varieties like Beefsteak and heirlooms tend to be the most susceptible.

Cherry tomatoes and paste tomato varieties with smaller fruits and thicker skins are generally far less susceptible to cracking.

Two types of splitting may occur:

• Radial cracks – Vertical splits from stem to bottom. Most damaging, as they expose inner flesh.
• Concentric cracks – Rings around the stem end, often not as deep. Less risky.

5 Ways To Prevent Tomato Splitting

Here are the top methods gardeners can use to minimize tomato cracking and enjoy more unblemished fruits:

1. Maintain Even Soil Moisture

Inconsistent watering is one of the key culprits behind fruit splitting. Tomato skins do not tolerate rapid expansions and contractions well.

Set up a drip irrigation system or diligently hand water to keep soil moisture as even as possible. Allow the top few inches to dry out between waterings, then deliver a deep watering.

Mulch around the base of plants also helps regulate soil moisture. Organic mulches like bark chips, straw, or compost will break down over time and improve soil health.

2. Provide Extra Calcium

Calcium strengthens cell walls, making them better able to handle quick growth spurts. Ensuring adequate calcium prevents cracking.

Mix calcium-rich materials into the soil like crushed eggshells, bone meal, or calcified seaweed before planting. These natural sources break down slowly, releasing calcium over time.

Spray a foliar calcium spray once fruits start forming. The leaves absorb the calcium, transporting it to the developing tomato where it fortifies cell walls.

3. Select Crack-Resistant Varieties

Some tomato varieties are naturally more prone to splitting, especially beefsteak types. Choosing resistant varieties avoids the issue altogether.

Opt for small-fruited varieties like cherry and grape tomatoes, which have thicker skins and are less susceptible to splitting.

Try heirlooms like Black Krim and Brandywine, which have fewer issues despite their large size.

Go for round varieties – tomato shapes with extra points and ridges (like oxhearts) are more prone to uneven growth.

4. Prune For Improved Air Circulation

Pruning away excess foliage allows better airflow which keeps humidity levels lower around plants.

Pinch out suckers – the small shoots that form between stems – to prevent overcrowding.

Remove lower leaves shading the soil to enable drying.

Space plants at least 2 feet apart to encourage air movement.

5. Pick Tomatoes Early and Often

Harvesting tomatoes before they fully ripen reduces the chances of splitting.

Pick one fruit to reach the mature green stage – when they are full-sized but still green with no blush of color yet.

Check plants daily and harvest promptly once fruits begin changing color. Leaving ripe tomatoes on the vine is when most splitting occurs.

Cut rather than pulling fruits off the vine to avoid damaging stems and neighboring tomatoes.

When Should You Pick Tomatoes To Prevent Splitting?

Knowing the optimal stage to harvest tomatoes makes all the difference in avoiding splits. Here are tips on identifying when tomatoes are ready for picking:

• Mature green – Tomatoes are full-sized but completely green and firm. Picking now prevents them from ever splitting on the plant. Allow to ripen indoors out of direct sun.
• Breaker – The first signs of color change are visible at the blossom end. Harvest now before splitting risk increases.
• Pink or turning – Up to 50% of the tomato skin has changed to its mature color. Pick immediately and ripen the rest of the way off the vine.
• Full color – Tomatoes are completely red, orange, purple, etc. Try to avoid letting fruits get this ripe before harvesting as splits happen most at this stage.

While you’ll get the most flavor and sugars allowing tomatoes to fully ripen on the vine, most gardeners find picking just before full color strikes the best balance for flavor while reducing splitting.

What To Do With Split Tomatoes

Even if you follow all the best practices, you’ll likely still get some splitting. Here’s how to make use of cracked fruits:

• Eat immediately – Use within a couple of days while still fresh and flavorful. The seeds and pulp are still OK to eat.
• Freeze – Remove splits and damaged portions, then freeze whole tomatoes or dice, sauce, or juice to use later in cooking.
• Can – Split tomatoes are perfect for home canning. The heat processing will kill any bacteria that enter through cracks. Dice, crush, sauce, paste, juice, or stew into jars.
• Dehydrate – Drying concentrates flavors and stops splitting issues in their tracks. Use slices in recipes all winter long.
• Feed to animals – Chickens, pigs, and other livestock relish tomato scraps. Just cut out splits and toss the rest into their pen.

While splitting tomatoes is frustrating, with a few simple practices put in place from the start of the season, you can minimize how many you get and still enjoy abundant harvests of perfect tomatoes.

Frequently Asked Question

A few more common queries about managing split tomatoes:

Final Thoughts

Preventing tomato splitting takes attention to growing conditions, plant health, and harvesting timelines. Pay special care to:

• Maintaining even soil moisture through drip irrigation and mulching
• Supplying adequate calcium via foliar sprays and soil amendments
• Picking crack-resistant varieties
• Pruning for improved air circulation and spacing
• Harvesting at the mature green and breaker stages before full ripeness

With vigilance in these key areas, you can minimize annoying tomato splits and enjoy bountiful harvests of gorgeous, unblemished fruits. Getting those growing conditions just right brings huge rewards at summer’s end.