If you are like me, you have been patiently waiting for that first juicy tomato from your garden. Then sadly, you go to harvest it and there is a problem with it. Maybe that problem is a crack, a rough spot on the bottom, discoloration, or deformation throughout the fruit.
So, what might have caused the crack? Tomatoes may crack open when excessive growth is brought on by rainy periods following a dry spell. This is something we may see in the coming weeks given the recent dry spell we have experienced. To reduce the chances of fruit cracking, we recommend watering regularly during dry weather, and potentially applying mulch to conserve soil moisture.
What may appear as a small crack, might actually be a zipper scar. A zipper scar is a thin, brown scar that starts from the stem end and goes fully or partially to the blossom end of the tomato. It mostly occurs during cool weather.
A rough black spot is one of many ways that individuals describe the problem of blossom end rot. Blossom end rot is actually a black, leathery scar that is on the blossom end (opposite of the stem) on the fruit. It most frequently occurs when we have extremes in soil moisture. This is something we have seen this growing season and have had a few calls into the Extension Office about thus far. The extreme variations in soil moisture can results in a calcium deficiency while the fruit develops which causes the rot to occur.
When your tomato has yellow streaking (when it is not supposed to), that is considered a discoloration. This discoloration is referred to as sunscald. Sunscald appears as yellow or white patches on the side of the fruit facing the sun. It is the result of immature, green fruit receiving excess sunlight exposure during hot weather. To prevent it, you would want to have good foliage cover.
Yellow shoulder is another discoloration issue that tomatoes can have. It is when the top of the fruit stays green or yellow while the rest of the fruit turns read. The cause of yellow shoulder is complicated, but it believed to be related to soil pH being too high, extreme high temperatures, poor foliage cover, and insufficient potassium.
Deformed tomatoes are often the result of catfacing. This generally occurs when days are cool and cloudy during fruit set resulting in the blossom sticking to the fruit and causing a puckering to occur. The cavities created by catfacing may penetrate deep into the fruit making it impossible to eat. Some tomato varieties seem to be more prone to do this.
Hopefully you are not facing any issues with your tomatoes. If you are, consider contacting the Purdue Extension Putnam County office at 765-653-8411 or e-mail smith535@purdue.edu with photos and information about the issue you are dealing with. We would be glad to help you identify the problem and hopefully prevent it from occurring in the future.