So you’ve spent months growing and nurturing your tomato plants, then suddenly one day you notice that the fruits are splitting – what is going on?! Tomato fruit splitting is a frustrating problem, but luckily one that is easy to solve too!

Why do tomatoes split?

As tomatoes grow, the skin needs to expand at the same rate as the flesh inside swells. If a split occurs, this is because the fleshy interior has expanded rapidly, normally due to heavy watering following a period of drought. This can lead to unsightly cracks in the skin surface or even a complete split down one side of the ripening fruit.

• Concentric cracks develop in a circular pattern around the stem, partially damaging the skin. These cracks often ‘heal’ themselves, sealing the fruit but leaving an area of scab-like skin.
• Radial cracks run vertically down the fruit and are normally full-thickness, exposing the flesh underneath. These deeper splits rarely heal and are prone to developing mould or fungus.

Split tomatoes are more commonly found in outdoor-grown crops after a period of heavy rain. However, even indoor-grown and irrigated tomato plants can develop split fruits if watering is not consistent.

How do I stop my tomatoes from splitting?

Tomato plants need soil that is consistently damp to thrive – applying one to two inches of water per week is enough to provide this, but it is the frequency of watering that makes the real difference.

Watering tomato plants deeply once per week will be sufficient to keep the plants alive, but the soil moisture will likely become so low between waterings that problems such as split fruit and blossom end rot occur. Conversely, watering a little bit every day is not sufficient to allow water to penetrate deep into the soil, and the plant will become stressed and prone to disease.

So, what is the solution? The most effective way to water tomatoes to prevent fruit splitting is to water deeply every other day or to use a drip irrigation system on a timer. In addition, check moisture levels regularly by scraping back the top inch of soil – if it is damp underneath, your watering schedule is perfect!

Should the soil ever dry out excessively, such as during heatwaves or periods of drought, water little and often for a few days until soil moisture levels return to normal. This will prevent the fruits from swelling too quickly and reduce the risk of them splitting.

Are tomatoes still good if they split?

Split tomatoes may still be edible, but must be harvested straight away as they can deteriorate very quickly. These damaged fruits can develop mould or fungus inside the split, attracting fruit flies and other insects that can damage the rest of the crop.

Inspect any split tomatoes carefully – if the broken skin is contaminated with dirt or you spot any mould or fungus, discard the fruit. Any remaining fruits can be carefully cut to remove the damaged section. These can be eaten raw or cooked but should not be used for canning or making preserves.

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