For a gardener, there is nothing more discouraging than being unable to stop the loss of tomato after tomato to blossom end rot. And chances are, if you’ve been gardening long enough, you have had the displeasure of experiencing it.
Blossom end rot occurs at the end of fruits as they develop and ripen. In essence, the tissue on the flowering end of the fruit rots away. In the process, it leaves behind an ugly brown scar. One that severely impacts the health and vitality of the tomato, and the plant’s overall yield.
Unfortunately, although it’s notorious for ruining tomato plants, it can also affect zucchini, squash, pepper and eggplant as well. It can be frustrating for sure. But, the good news is it can usually be prevented with a bit of extra care.
Blossom end rot is not a disease or an infection that spreads from plant to plant. Nor is it a soil borne issue like tomato blight that lies in wait to return year after year. Instead, it is caused by one simple problem – a lack of calcium being absorbed by the plants.
Many who deal with blossom end rot assume the issue all stems from lack of calcium in the soil. And many times, that is indeed exactly the case.
But it’s important to note that in addition to a lack of available calcium, there can also be other underlying conditions or issues that can prevent your vegetable plants from absorbing the vital mineral. Even when there is plenty of calcium already in the soil.
Here is a look below at the various causes of calcium deficiency, and how to correct it for healthy, productive plants.
How To Stop Blossom End Rot
Lack Of Calcium In The Soil
As mentioned above, a lack of available calcium in the soil is often the main issue when dealing with blossom rot. And there are several ways to correct the issue to make sure your plants always have plenty on hand.
First and foremost, the practice of crop rotation is vital in keeping calcium at the ready for plants. In fact, crop rotation is extremely important for keeping all of the nutrients plants need for strong, healthy growth in good supply.
Vegetable plants feed from the soil as they grow and develop. And whether it be corn, beans, lettuce or tomatoes, each vegetable uses a different set of nutrients to thrive. But by moving these crops around, the soil has a chance to replenish what might have been taken from the plants that grew in the space previously.
The simple fact of the matter is if you plant the same plant variety in the same soil space year after year, the soil will eventually run out of nutrients that specific plant needs. Case in point, calcium for tomatoes.
Rotating Your Tomato Crop
But by rotating your tomato crop each year, you can help alleviate the issue. For best results, rotate your tomatoes so that they never grow in the space for at least three full seasons. For potted tomatoes, changing out the soil ever year is a must!
In addition to crop rotation, you can also build in calcium to the soil as you plant. One of the best ways to do this is by adding crushed egg shells while planting. Three to four egg shells crushed up finely and added around the roots of young transplants will do the trick.
As the plant grows, the egg shells decompose and give back calcium to the soil which can the be absorbed by the plants. In addition to egg shells, you can also add bone meal or lime to the soil to increase calcium levels.
Additional Causes Of Blossom End Rot
As mentioned before, many times, there can be calcium present in the soil, but the plants simply can’t take it in. When it comes to this issue, there are usually 3 main culprits : over/under watering, over-fertilizing and compacted root systems. Here is a look at each, and how to stop and prevent them from causing blossom end rot.
Over/Under Watering
Both over and under-watering play a huge factor in causing blossom rot. When a plant receives too much water, the roots are simply unable to take in nutrients. As they swell with water, they lose their ability to absorb. The same goes for when the roots shrivel from drought-like conditions. That is why proper watering is vital!
Tomatoes should receive around an inch of water per week to help develop healthy root systems. If your plants begin to turn yellow, it’s a sign that over-watering is occurring. Likewise, if plants are wilted and the leaves are curling up, there is not enough water in the soil for the plants to grow and develop.
When you water, it’s more important to water deeply than more frequently. Frequent, shallow watering does not allow the roots to grow deep into the soil. Not only does it lead to the roots drying out too quickly, it also means the roots are not deep enough to get to more of the calcium in the soil.
Compacted Roots
Another way tomato plants have difficulty absorbing calcium is when their roots are compacted in the soil. Packed soil suffocates the tiny intakes within the root nodules. When this happens, the tomato plants can’t absorb water or nutrients.
Keep foot traffic around plants to an absolute minimum. Especially within 12 to 18 inches in diameter around each plant. This allows the soil to remain loose and free for easy nutrient intake.
Over Fertilizing
As the old saying goes, too much of a good thing can be a bad thing. And that is certainly the case when tomato plants are over-fertilized.
When tomatoes receive too heavy of a dose of nitrogen magnesium and phosphorous, they can crowd out the intake of calcium. The result, heavy top growth and a mess of tomatoes with blossom end rot! Fertilize low and slow with tomatoes to keep steady but not overpowering growth. See: How To Fertilize Your Tomatoes!
Early Season Blossom End Rot
One final not about blossom end rot. In the early spring, it is quite common for the first few tomatoes on a plant to show some signs of blossom end rot. This is actually caused from the initial stress of fruit production, and not always a sign of a calcium deficiency.
Simply pick these first few tomatoes off the vine and allow the plant to settle in to normal production. If the problem persists into the second or third week, then it’s time to consider a calcium issue being the problem.
Here is to stopping tomato blossom end rot, and to a great tomato harvest this year!
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