3 Tomato Plant Problems and How to Prevent Them

Keep Your Tomatoes Healthy

Tomatoes on Vine

Marie Iannotti

Every gardener will experience some problems when growing tomatoes. To some extent, your success as a tomato gardener is dependent on the weather and other conditions that are out your control. However, knowing what you are dealing with can make your tomato growing more successful. These common tomato problems can be addressed while your tomatoes are growing or, even better, prevented before they start.

  • 01 of 03

    Tomatoes That Turn Black and Soft on the Bottom (Blossom End Rot)

    Blossom end rot on beefsteak tomatoes (Solanum lycopersicum) caused by irregular watering
    John Beedle / Getty Images

    There may be no tomato problem more heartbreaking than blossom end rot because this tomato problem doesn't show itself until the tomato begins to ripen. By then, it's too late to do anything about it. What's more, all the tomatoes that are currently on the plant are probably going to follow suit.

    Blossom end rot is not a disease. It is thought to be caused by insufficient calcium. However, don't rush out to by a calcium supplement for your soil. This calcium deficiency is probably caused by irregular watering and fluctuation in water levels.

    Plants rely on water to carry nutrients, like calcium, throughout the plant. When a tomato plant receives insufficient water, the nutrients will first go to the foliage and may not make it all the way to the fruits. That is why it's so important that your plants get at least 1 inch of water a week, every week. You can't make up for a couple of dry weeks by finally giving your plants a deep watering. The damage is done by then.

    Besides insufficient or irregular water, blossom end rot can also be exacerbated by a handful of problems including these:

    • Excessive nitrogen fertilizer will cause a lot of leafy grow and divert nutrients away from the fruits.
    • To much salt in the soil, will inhibit the uptake of water. High levels of salt are often caused by excessive use of synthetic fertilizers.
    • Root damage also restricts the uptake of water. Roots can be damaged by animals or cultivating.
    • Soil pH can be either too high or too low for the tomato plants to access the nutrients in the soil. Tomatoes prefer a soil pH around 6.5.

    While you cannot save the fruits that already have blossom end rot, you can salvage the rest of the season by being vigilant about watering, mulching around the plants to conserve moisture, and correcting any other problems.

  • 02 of 03

    Tomatoes That Crack as They Ripen

    Ripe red tomato with split in skin
    Dorling Kindersley / Getty Images

    Otherwise healthy looking tomatoes split open before they're even fully ripened. What happened, how can you stop it from happening, and are they still okay to eat?

    Tomatoes tend to crack when they are not watered regularly. Often when tomatoes experience a prolonged dry spell, we try to make up for it with excessive watering. This causes the pulp inside the tomato to hold the water and swell faster than the outside of the tomato can stretch. When that happens, the outside of the tomato splits open, causing cracks.

    The good news is that the tomatoes are fine otherwise and perfectly edible. However, you will need to use them immediately, because the cracks will start to develop mold.

    To prevent cracking, make sure your tomato plants are getting regular water. That can be hard to do when there is excessive rain, but you can still moderate things by watering weekly when the weather is dry. A 4–6-inch layer of mulch will help keep the soil around the roots moist, further moderating the moisture level in the plants.

    If cracking is a major problem, look for varieties that are labeled as crack resistant. Some good ones to try include Celebrity, Pruden’s Purple, and Sun Gold.

  • 03 of 03

    Tomatoes That Never Fully Ripen (Green Shoulders)

    Tomato with Green Shoulders
    Alfi007 / Stock.xchng.

    You can wait and wait some more, but some tomatoes are never going to fully change to red. This is not the same as that frustrating wait for green tomatoes to ripen at the end of the season. Tomato "Green Shoulders" is a condition in which the majority of the tomato ripens, but the area near the stem remains stubbornly green and hard. There's also a similar condition called "Yellow Shoulders", which occurs when lycopene production slows down.

    These conditions are a bit more complicated than the two tomato problems discussed above. Sometimes it's just the type of tomato you're growing and sometimes the weather and sunlight play a hand. To prevent the problem, be sure your tomatoes have a bit of shade and pick the tomatoes early if you're experiencing intense heat.

    While green shoulders are disappointing, the portion of the tomato that has fully ripened should still be delicious and is fully edible. Just slice off the green portion and no one will be the wiser.