Blossom End Rot: Learn Identification, Prevention and Treatment

Blossom End Rot (BER) is a common physiological plant disorder.

You have probably noticed blossom end rot of tomato fruit or other fruits and vegetables with the bottom turning black.

rot blossom end tomato

If you have, you are probably already familiar with BER.

While it is a common problem mostly associated with tomato plants, this disorder also affects peppers, eggplants, squash, watermelons, and various other plants.

This makes it important to learn all about it.

What Is Blossom End Rot?

BER is described as calcium deficiency in plants a physiological disorder. Calcium for plants is an important mineral essential for both the health and growth of most plants.

No wonder its deficiency can cause plants to develop serious conditions at the blossom end of the fruit.

Keep in mind that deficiency in calcium can be caused due to a number of reasons.

Some common culprits behind BER include:

  • Moisture stress from low soil moisture or water shortage which disrupts the transportation and nutrient uptake of the minerals (causing a lack of calcium) in the plant
  • Using a high nitrogen fertilizer (with high salt levels) causing too much nitrogen in the soil, which makes it impossible for the plants to uptake adequate amounts of calcium through the stems. Organic gardeners using egg shells as a calcium source may not provide plants with enough.
  • This problem can also arise due to poorly drained soils.
  • Acidic, coarse, and sandy soils can also lead to developing blossom end rot in plants as they contain low calcium levels.
  • Planting of crops too early such as tomatoes in cold soil hindering root development and damage to root systems.

On the other hand, plants and developing fruit can experience BER even when there is a sufficient amount of calcium in the soil.

The reason is that while there is enough calcium present, it may be in an insoluble form, making it difficult for plants to absorb it.

Keep in mind that while Blossom-nd rot is a common home garden problem, it is not a plant disease. It is merely an imbalance of nutrients within the plant.

The dark brown spots are often found on the first fruits of the season including the popular Roma variety.

What Damage Does Blossom Rot Cause?

BER works by damaging the localized tissue of the plant. This results in stunted plant growth that eventually destroys the affected fruits. of buds and rot tips.

Once the plant is affected, it is common to notice water-soaked spots that appear on the bottom of fruits or vegetables.

In fact, this is where the name of this plant disorder, Blossom end rot, is derived from.

The damage first appears on the fruits when they have grown to at least half of their full size.

That’s when you will start noticing the black patches at the blossom bottom of the fruits.

In just a few days, the water-soaked patched will turn leathery and grow in size. Eventually, they start to rot, making it impossible to consume the fruit or vegetable.

How To Control Blossom End Rot

Sure, Blossom end rot is not a plant disease but it is equally deadly.

This makes it important to take preventative measures to make sure your plants don’t develop it.

In case, the plants are already affected, take right measures to reserve the damage and restore your plant to health.

Here’s a list of control measures you can take to control Blossom-End rot.

  • Maintain the soil pH level around 6.5 to make sure it is not acidic for the plants. At the start of the season have a soil test done.
  • Take your time to pick the fertilizer. Choose ones low in nitrogen and a high percentage of phosphorus. Such fertilizers ensure to reduce the chances of BER.
  • Make sure your plants enjoy a consistent level of moisture in the soil during the growing seasons. Use a soaker hose to irrigate the vegetable garden. More on soaker hoses.
  • It is advisable to use well-drained soil. We like growing in raised beds to better control soil quality.
  • Before planting, make sure that the ground is not too hard due to cold as that makes it difficult to absorb calcium from the soil.
  • Regularly apply mulch (like wood chips or grass clippings) to help maintain even soil moisture.
  • Avoid any deep cultivation around plants to prevent potential root damage once the fruit set starts.

NOTE: Applications of calcium sprays such as calcium chloride have been reported to provide minimal to temporary relief of BER.

Remember, it is possible to get rid of Blossom end rot. However, you have to act quickly in order to save your crop before the damage gets out of hand!

Articles across the internet recommend using Epsom salt to stop tomato blossom rot – Not True! Learn why

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