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Can Tomatoes With Blossom End Rot Be Eaten

Tomatoes are vulnerable to several pests and diseases, and therefore, they are known to be challenging plants to grow. One common condition that gardeners experience with their tomato plants is blossom end rot. It can be some of the greatest disappointment for a gardener to find these unappetizing areas develop on tomatoes that previously appeared to be ripening healthily. While many questions and guidance come with blossom end rot, one common question is, can tomatoes with blossom end rot be eaten?  

While a tomato with blossom end rot is partially rotten, the condition is localized to one area of the fruit, and the rest of the tomato is indeed still edible. You can slice off the section of the fruit with blossom end rot and still enjoy the rest of your tomato.  

Read on to learn more about blossom end rot and ways to prevent it.  

More About Blossom End Rot

Blossom end rot is a disease developed by plants with a calcium deficiency. While it is most common in tomatoes, the disease has also been found in squash, peppers, and eggplant, though less often. The calcium deficiency caused by blossom end rot can come directly from the soil.

It can also be connected to the moisture levels in the soil that are needed to transport nutrients, including calcium, throughout the entire plant. When the soil lacks calcium altogether, the deficiency affects the whole plant.

Suppose the issue is that there is calcium in the soil but not enough moisture to distribute it through the entire plant. In that case, calcium deficiencies may be more localized. Either situation can result in blossom end rot.  

Typically blossom end rot will first appear on ripening tomatoes at any point from when the fruit is still green to when it is reddening and close to harvest. What is often first noticed looks like a water spot on the fruit, and then as the blossom end rot develops, the area begins to sink in and darken in color.

While these rotten areas do grow in size, they stay contained so that most often, more than half the tomato remains unaffected and edible. Although blossom end rot can be an annoyance for gardeners, there are ways to maintain and prevent it.  

4 Ways To Prevent & Treat Blossom End Rot

Blossom end rot can be quite annoying, thankfully there are a couple options you have to prevent it.

Maintain Soil & Plant Hydration Levels

As explained previously, blossom end rot results from a calcium deficiency within the plant. While there may be plenty of calcium in the soil, if there are irregular moisture levels from drought-prone environments or inconsistent watering, it can create a situation where there is not enough moisture to move the calcium from the soil fully through the plant.

Even though these calcium deficiencies may not affect the entire plant, they can still result in blossom end rot.  

Blossom end rot is not only caused by too little watering. It can also result from too much watering. If there is calcium in your soil, your tomato plants will get a healthy supply of it with a consistent watering schedule, preferably in the evening after the day’s heat has passed so more moisture can be absorbed by the plant instead of evaporated by the sun.

Using ground cover such as mulch creates a safety barrier for your soil from many outside elements while also holding its nutrients. Mulch can be a preventative measure with blossom end rot because it helps keep moisture in the soil longer, creating an environment where the roots can hydrate the plant and distribute soil nutrients more successfully between waterings.  

Soil Temperature

Just as with inconsistent watering, drastically varying soil temperatures can also affect the calcium distribution within your tomato plants.

Regardless of the growing zone in which you live, tomato plants will grow most successfully in environments and seasons where soil temperatures remain 55 degrees or higher from planting outdoors through harvest. Unseasonably cool temperatures can reduce the distribution of calcium from the soil throughout the plant.  

The best way to avoid an unhealthy dip in soil temperature is to know and follow the plant hardiness zone for your geographical area. These zones provide a guide for gardeners to know when average temperatures are safely warm (or cool) enough to plant specific plants.

While it is not always a guarantee, following the advised planting schedule for your geographic zone will often result in consistent soil temperatures, helping to prevent blossom end rot.  

Soil Fertilizer and Nutrients

It’s important to know what is in the nutrients and fertilizers you are feeding your tomato plants. Some fertilizers are high in nitrogen, which can harm your tomatoes and potentially even make the blossom end rot on already affected tomatoes worse. When researching fertilizers for your tomatoes, focus on organic products lower in nitrogen and higher in superphosphates.  

Purchasing a soil test to assess the pH levels can help you identify your specific soil needs before selecting a fertilizer. A soil pH level between 6.5 and 7.5 is ideal when growing tomatoes. A tomato plant growing in soil outside this range is more susceptible to blossom end rot.

Nitrogen most affects the soil’s pH level, and there are varying levels of acidity within the nitrogen umbrella. Ammonium-based fertilizers have high levels of nitrogen, resulting in higher acidity. Nitrate-based fertilizers are known to be less acidic.

Phosphorus fertilizers are mostly lower in nitrogen levels, so they typically also have little effect on the pH of the soil. Knowing your soil pH level and picking a fertilizer that will help maintain or reach the ideal pH is an essential step for preventing blossom end rot.  

Tomato Variety

There are thousands of tomato varieties globally, and it’s impossible to know them all. However, a few common tomato varieties are known for being more prone to develop blossom end rot than others. Beefsteak, Roma, and Pear varieties are more likely to suffer from blossom end rot than other varieties. Many online resources are available to help you select tomato plants with higher resistance to blossom end rot.

Final Tips on Blossom End Rot

All of the methods described in this article can help prevent blossom end rot and work as treatments if your plants are already showing signs of the disease.

For those plants that are already showing signs of blossom end rot, the most critical step is to remove all infected tomatoes immediately. Prompt removal of the rotting tomatoes makes it more likely that the remaining tomatoes on the plant will stay healthy, and you will save at least some of your harvest.