Growing a healthy and bountiful garden is a dream of all gardeners. No matter what your reason is for growing a vegetable garden, you want to grow loads of pretty vegetables. It can be a bummer when blossom end rot rears its ugly head in your vegetable garden. Let’s talk about what blossom end rot is and how to prevent it.
What is blossom end rot?
Blossom end rot shows itself as a nasty, dark colored lesion on the blossom end of vegetables. It is most commonly seen as a dark, wet-looking spot on tomatoes, squash or peppers. Although these are the most common plants to develop blossom end rot, they are not the only ones that can be affected. Any vegetable that develops from a bloom can technically end up with blossom end rot.
The tissue at the blossom end will develop a lesion that is dark brown or black and looks wet. The blossom end is the end furthest from the stem of the plant.
Blossom end rot doesn’t usually result in an entire fruit that is covered with a lesion, but it can create a rotten bottom that can cover up to half of the fruit. Affected squash will shrivel and turn pale yellow if they develop blossom end rot.
The lesion that develops due to blossom end rot creates an open wound. This open wound allows pathogens like bacteria and fungi to enter the fruit and cause further damage. If you’ve ever cut up a vegetable that had blossom end rot and it looked moldy or shriveled inside, then the vegetable likely had a secondary infection going on due to the open wound that the blossom end rot created.
What causes blossom end rot?
Blossom end rot may look like a nasty infection of some kind, but it’s not an infection at all. Blossom end rot is actually the result of a calcium deficiency in plants. Calcium is a nutrient that plants need. Calcium is used to promote healthy bloom and fruit development. Without enough calcium, fruiting vegetable plants will not be able to develop correctly and blossom end rot occurs.
Calcium deficiency can be caused in a few different ways. Calcium is a necessary nutrient that plants need, but it is difficult for many plants to obtain and use efficiently.
The main cause of calcium deficiency, and thus blossom end rot, is due to a lack of calcium in the soil. If there is not enough calcium in the soil, the plant cannot take in what it needs.
Sometimes, there is ample calcium in the soil but the plant cannot absorb it properly. Calcium is absorbed through the same channels that magnesium, potassium and ammonium are absorbed. All of these are necessary nutrients that plants need.
Since they are all absorbed the same way, they can sometimes compete with each other to get taken up by the roots. If there is too much magnesium, potassium or ammonium in the soil, calcium won’t be absorbed in high concentrations and blossom end rot will occur.
Other external conditions can prevent calcium from being absorbed. Drought conditions and lack of soil moisture can prevent calcium from being absorbed. Too much soil moisture, or waterlogged roots, can keep calcium from being absorbed also.
A fluctuation in soil moisture also affects how well calcium is absorbed. Since calcium is absorbed through the roots, any damage to the roots can disrupt calcium absorption.
Calcium is also hard to move through the plant. This sounds silly, considering how critical calcium is to proper reproduction for the plant. With that being said, it is difficult for a plant to move calcium from the leaves to the fruit where it’s needed. It can be even more difficult for a plant to move calcium up from the roots, through the stems to the fruit where it’s needed.
The amount of humidity in the air and the wind can disrupt the rate of transpiration, which affects how well the plant can move calcium from the leaves to the blossoms and fruit.
Keep in mind that today’s vegetable plants are very high-yielding and under constant stress to produce. This constant stress keeps the internal plant systems working hard, including the systems that are responsible for moving calcium.
How you can prevent blossom end rot
Now that you know what causes blossom end rot, let’s talk about how to prevent it. Since blossom end rot is another name for calcium deficiency in plants, the obvious treatment and prevention is to provide calcium.
You may not know the exact cause of blossom end rot in your plants unless you have a soil test done. You may not know if your soil has calcium or if the soil has other nutrients that are competing with calcium. A soil test can give you a better understanding of why your plants are developing blossom end rot. However, although a soil test can be beneficial, it can be time consuming. If you’re in the thick of growing season, you may not have time to wait on the results from a soil test.
The easiest way to treat blossom end rot during the growing season is to use a foliar spray like the Bonide Tomato and Blossom Set Spray. This ready to use spray can be sprayed directly on the leaves, blooms and fruit. Not only will it help create healthier blossoms and fruits, but it’s been shown to improve the quality of the fruit also.
Bonide’s Tomato and Blossom Set Spray can decrease the amount of time it takes for your plants to develop fruit. Some gardeners have noticed that Bonide’s Tomato and Blossom Set Spray has helped to mature their tomatoes as much as 3 weeks faster!
If you’re looking for the perfect way to prevent blossom end rot and increase the overall productivity of your tomato plants, this is the tool you need. Your tomatoes and other blossom end rot plagued plants will thank you. Use it safely in all gardens and on all plants that could develop calcium deficiency and blossom end rot.
Many calcium supplements for plants are sold in a concentrated formula and have to be mixed with water. The Tomato and Blossom Set Spray is pre-mixed, so no measuring and guessing is required. Simply spray your tomato and vegetable plants and harvest the prettiest fruit you’ve ever grown.
Blossom end rot can creep up on you each year, so it’s a good idea to amend your soil if needed. Crushed eggshells, limestone and gypsum can add calcium to the soil. Always have your soil tested before amending the soil to make sure that you’re adding the proper amendments. Remember, just because your plants develop blossom end rot doesn’t mean that your soil is lacking calcium. A soil test is the best way to determine the cause.
This post was written by Shelby DeVore, the founder of Farminence. Shelby is a passionate gardener with 20+ years of experience gardening and growing food at home. She currently lives in West Tennessee on a 14-acre homestead with her husband, three children and too many animals to list.