Blossom end rot peppers

About Kristen Raney

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You’ve planted the tomato seeds, watched them grow, and now you’re finally starting to get some beautiful tomatoes! But what’s this? Who put this disgusting black scab on the bottom of my beautiful tomato?

That horrible scab that’s ruining your tomato is called Blossom End Rot.

Blossom end rot is caused by two things: a lack of calcium and inconsistent watering. While the best cure to blossom end rot is prevention, it can be reversed once it’s started.

Here’s how.

Step 1: Remove all Affected Tomatoes

Unfortunately, once a tomato has blossom end rot, it won’t go away. However, you can still save the plant and any remaining tomatoes it produces. Put all rotten tomatoes in your compost and cut your losses.

Step 2: Water with Powdered Milk

Those tomatoes need some calcium at the root–stat. While egg shells are great, their calcium won’t be picked up by the plant until they start decomposing. That’s great for a few months from now, but doesn’t help your problem. Instead, mix powdered milk into your watering can for a quick hit of calcium that doesn’t resort to using lime. Lime should only be used if you know you have a soil PH problem.

Related: The Best Tomato Varieties to Plant for Your Gardening Situation

Step 3: Water Every Day, Twice a Day in Extreme Heat

Tomatoes need consistent water. In fact, skimping on watering earlier in the month is likely what caused blossom end rot in the first place. Last year when my tomatoes succumbed to blossom end rot (due to inconsistent watering because we were renovating our bathroom and not living in our home) it took two weeks of daily watering (unless it rained) to reverse the problem.

Thankfully, I still ended up with the lovely tomatoes you see in all the pictures in this post.

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Optional: Use Mulch to Further Prevent Blossom End Rot

Finally, if you want to hold in the moisture in your soil, surround your tomatoes with 2-4 inches of shredded newspaper or wood chips. This easy organic mulch will retain moisture, prevent weeds, and add more nutrients to the soil over time.

Related: How to Use Mulch in the Garden for Easy Weed Control

There you have it! Blossom end rot isn’t fun, but you don’t have to let it ruin all your hard work in the vegetable garden.

P.S.- There are actually a couple more reasons why your plants may have blossom end rot–I’ve chosen to focus on this reason and solution because not watering enough is usually the culprit 80% of the time. If my process doesn’t work, you’re unfortunately in the other 20% and will need to do some further research into why its happening in your garden.

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Kristen is a former farm kid turned urban gardener who owns the popular gardening website, Shifting Roots. She is obsessed with growing flowers and pushing the limits of what can be grown in her zone 3b garden. She also loves to grow tomatoes, but oddly enough, dislikes eating them raw.

Prevent blossom-end rot

Blossom-end rot is a very frustrating environmental disorder of tomatoes, peppers and, less often, eggplant. The disorder is characterized by the far end, or the blossom-end, of the tomato, developing a black, water-soaked spot that expands and rots. This rot ruins the fruit and makes it unsuitable for eating.


Blossom-end rot. Photo credit: William M. Brown Jr., Bugwood.org

What causes blossom-end rot?

The cause of this rot is insufficient calcium in the fruit to form cell walls. The conditions that cause blossom-end rot are closely linked to inconsistent soil moisture (too wet or too dry) throughout the growing season. Calcium can only be moved into the fruit during development with an ample moisture supply. Too much water can also prevent calcium movement.

Other factors that can limit a plant’s ability to absorb enough calcium for proper fruit development include root damage due to cultivation, excessive nitrogen in the soil, cold soil or soil high in salts.

Suggestions for prevention

To prevent blossom-end rot, be sure there is an even moisture supply and never let the soil dry, then overwater, dry and then overwater. Mulching will help keep moisture levels even. However, mulch only with organic materials (not stone) and wait to mulch until after the soil has warmed up. Soil in southern Michigan usually warms up by mid-June. Don’t over fertilize, especially early in the season.

For small gardens, a method to ensure good drainage while retaining adequate moisture is to plant your tomato plant on a mound of soil with a high percentage of organic matter or compost. The organic matter will retain the moisture, while the elevation of the mound will provide good drainage. The elevated, darker colored mound will also warm up quicker.

Blossom end rot affects mainly tomatoes and peppers, but can affect other fruiting crops such as eggplant, watermelon and summer squash. This is a perennial problem, meaning that as a gardener, you will deal with this yearly in your garden. There are two approaches to working with blossom end rot – prevention and reaction, or a primary and secondary solution. Unfortunately, most gardeners only realize they have a problem when the fruit are showing black spots on the end. This is the acute phase – once there are problems – and immediate action is needed to prevent further damage to fruit that is just beginning to set.

We will look at the underlying causes of blossom end rot, along with what happens and what can be done about it in the prevention as well as the acute phase.

As mentioned, blossom end rot will affect more than just tomatoes and peppers, but we will focus mainly on those as this is what most gardeners’ experience. Just tuck the other varieties into the back of your mind, and you’ll have a jump start if you see it strike them. In reality, the prevention will most likely have a beneficial effect for everything as you will be creating an environment that won’t support the cause of the problem!

Blossom end rot is caused by a lack of enough available calcium in the fruit at the blossom end. What most often alerts us is a black spot or patch at the blossom end of the tomato or chile, opposite of the stem. This black spot is a secondary issue caused by a fungus attacking the weakened fruit. Contrary to what many think, we aren’t aiming for the eradication of the fungus and resulting black patch, but fixing and preventing the cause of the problem. Correcting the underlying issues that lead to the weakened fruit will automatically prevent the fungus from being able to attack.

Let’s start with the problem and work backwards, to better understand what is needed for both an acute fix and a preventative approach for blossom end rot. Calcium is a very important part of the growth process for plants and the proper development of high quality, tasty fruit as it contributes to healthy cell wall growth, insect resistance and helps to regulate many cell processes. Calcium is non-mobile in the plant once it is imported, meaning the plant can’t move it from one part of itself into the fruit, or from one part of the fruit to another. Thus, the tomato or chile plant needs a continuous supply of calcium as it grows, flowers and produce fruit all through the season.

Blossom end rot usually occurs early in the season with the first or second flush of fruit. It happens just when the plant is at maximum growth and is putting on the first fruit, with a second set of flowers on the way. It is in high gear and needs all of its nutrients available to be healthy, resist pests and disease, as well as grow lots of delicious tomatoes and peppers. The key to preventing blossom end rot is to supply a sufficient, steady amount of calcium to the plant so it can be transported into the fruit continuously. Problem solved!

Not so fast, just how can we make sure that the plant has a steady supply of calcium?

Early Blossom End Rot

Here is where we branch off into the two approaches – the primary and the secondary. The primary, preventative approach is to have enough calcium in the soil that feeds the roots and is transported to the fruit throughout the growing season. That calcium in the soil must be ‘available’ meaning that the roots can actually absorb it and transport it where it is needed. Available means that it isn’t tied up by another mineral or a pH level that won’t ‘let go’ of it. There is more to the story than just adding a calcium amendment to the garden bed!

A very good example of this is where we live in central AZ, there is a decent amount of calcium in the soil that plates out on faucets and glassware as a calcium deposit. Conventional wisdom says not to worry about calcium because it is everywhere. That’s true, but the challenge we have is the pH of the soil is fairly alkaline at 8+ on the pH scale, so the calcium is ‘tied up’, or not available to the plants. This is proven by the weed populations we typically see that only grow in calcium deficient soils.

So what can be done? A comprehensive soil test is one of the best, first steps to take. This is much more than the simple NPK type of test done by university extension offices or the do-it-yourself test kits bought at the local garden center. A complete soil analysis is one that is collected and sent off to a recognized, professional lab that sends back a report on every mineral found along with recommendations on what direction to go and what nutrients to add in what form. They will usually cost from $25 to $75 range, depending on what analysis and information you need. There are several of these labs in the US; the two that we’ve worked with and are familiar with are Crop Services International and Texas Plant and Soil Lab. From this, you will have a very good indication of where to go next.

Fall is a great time to get your soil tested and amended in preparation for next spring’s season for a few reasons – the soil testing labs are generally not as busy, so results are quicker; and soil amendments will need some time to become integrated and available into the soil nutrients, so fall gives you the needed time, and it is easily incorporated into the traditional fall garden cleanup and prep.

Calcium is closely tied with magnesium, and this will be indicated on the soil analysis. More acidic soils, such as those generally found in the eastern states, will benefit from lime or calcium carbonate, while the more alkaline soils in the western states will need gypsum or calcium sulfate. Lime tends to raise the pH, while gypsum tends to lower it.

Water plays an often overlooked, but equally important, role in the blossom end rot saga. Inconsistent levels and rates of water will greatly vary the amount of calcium and other nutrients available to the plant, increasing the chance of diseases attacking the fruit like blossom end rot. This is one of the reasons we talk a lot about a drip system on a timer – it really helps even out the moisture levels in the soil and greatly reduces the stress on the entire garden, with the happy result of lowered amounts of nutrient and stress related problems. Of course, the weather can also play havoc with all of our carefully laid plans, as heavy and sudden rainfall can cause blossom end rot and splitting of tomatoes, along with a noticeable ‘wash-out’ of flavor and taste.

This is where the acute or secondary approach is needed. Calcium carbonate tablets, or anti-acid tablets (Tums or the equivalent) work great when a couple of them are inserted at the base of a tomato or chile plant, where they will dissolve and make the calcium available to the plant in just a few hours, saving this flush of fruit if done right after the rains, or the next set if done when blossom end rot is first noticed.

Another approach is to feed calcium directly to the roots through the drip system as a liquid fertilizer, usually with calcium chloride or calcium nitrate. This approach works very well in offsetting one of the most overlooked causes of blossom end rot – great weather. That’s right – excellent weather with moderate temperatures and lots of sunshine put the plants into overdrive, and their rapid growth can often simply outstrip the amount of available calcium in the soil, even if you have been proactive last fall. The calcium just cannot be taken up out of the soil fast enough, so feeding through the drip system can be a big bonus during these times. The secondary approach will always be needed, even if you’ve done your homework and amended the soil the previous fall.

Calcium isn’t absorbed very well by the leaves of a plant, especially older leaves. The roots are much better at absorption, plus they can transport the calcium faster than through a foliar approach. For these reasons, stay away from trying a foliar spray to supply calcium to your tomatoes.

Blossom end rot won’t ever quite go away, because of the reasons you’ve seen here. With some knowledge and practice, you can easily create a much better environment in the soil that supports the plants much more fully and then use the supplemental approach to keeping the calcium levels high enough to minimize blossom end rot and keep more of your hard work for your dining table instead of as scraps for the chickens or compost pile!

Brown spot on Bell Pepper

Hello and thank you for using ask an expert. I think that a calcium deficiency is exactly what is causing your issue with the peppers. A soil test will determine if it is a soil issue, since calcium availability can be affected by very acidic soil be sure to ask for a pH test in addition to information on soil mineral content. Calcium deficiency can also be caused by uneven watering. If water is not readily available for carrying the calcium to the plant evenly it can result in a localized deficiency in the fruit as it grows and cause blossom end rot. Our unusually hot weather this year makes it harder to achieve the ideal amounts of water being available in our garden soils at all times. While peppers like well drained soils they also need to be kept evenly moist. You did not mention fertilization of your crop, an application of too much nitrogen can exacerbate the problem as it causes the plant to grow rapidly making it harder to keep that calcium getting to where it is needed.

Get a soil test to determine if calcium needs to be added. Add lime, preferably in the fall. Mix in the lime thoroughly into the top 8-12 inches of soil. Try to achieve a pH of 6.8 to 7.

Fertilize plants moderately. Plants should be vigorous and green but not luxuriant. Side dress with nitrogen only if required to maintain color and moderate growth.

Consider mulching plants (with black plastic or organic matter) to aid with keeping soils moist in hot weather. Provide even moisture throughout fruiting by controlled watering and mulching. You can check for soil moisture by digging down and checking for water penetration the day after watering.

6 Common Tomato Troubles and How to Fix Them

Everyone loves mouthwatering homegrown tomatoes, but too often gardeners are disappointed when their crop develops problems. Here’s a quick rundown of common tomato ailments and how to treat them.

Blossom End Rot

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Symptoms: Blossom end rot occurs when a sunken rotten spot appears on the bottom end of the fruit.

Causes: Blossom end rot is caused by a lack of calcium, resulting in the tissues at the end of the fruit breaking down. A shortage of calcium can develop if the soil is low on the chemical or if the calcium in the soil is tied up due to low soil pH. It also could be due to inconsistent watering or drought that limits how much calcium is absorbed by the plant.

Solutions: Start with a soil test. If your soil has low pH you might need to add lime to the garden. The best pH for tomatoes should be between 6.5 and 6.8.

Also, mulch your plants to maintain consistent soil moisture. Vegetables require 1 to 1-1/2 inches of water a week, so use a soaker hose to deliver water directly to the root zones of the plants. And finally, don’t overfeed your plants. Fertilizers with high nitrogen content bind the calcium in the soil, making it impossible for the plant to absorb.

Cracking

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Symptoms: Cracking occurs when the skin of mature or nearly mature tomatoes splits either in concentric circles or radially down the side of the fruit. The fruit remains edible, but the cracked portion of the tomato must be cut away. Insects also can attack the fruit through the cracks.

Causes: Some varieties of tomatoes are more susceptible to cracking than others. Cracking occurs when the plants have periods of very fast growth followed by slow growth and then fast again. The cells in the tomatoes skin can’t stretch fast enough and cracking occurs. Dry periods followed by heavy irrigation or rainfall is one of the main causes of cracking.

Solutions: Mulch tomato plants to encourage consistent soil moisture. Also, do not over fertilize the plants to encourage fast growth. When selecting tomato varieties look for those that are listed as crack resistant.

Tobacco Mosaic Virus

Symptoms: Plants suffering from tobacco mosaic virus have mottled foliage with alternating yellow and green areas. The green areas also might be raised or blistered. The fruit will also be misshapen with patches of lighter areas over the skin.

Cause: Tobacco mosaic is generally transmitted by humans who have had contact with tobacco products or by insects that have been feeding on tobacco plants. When a tomato is handled during planting or harvesting, an open wound occurs that allows the virus to pass into the plant.

Solutions: If you smoke, always wash your hands thoroughly before you touch tomato plants. There is no cure for tobacco mosaic, so remove plants immediately if symptoms appear. Avoid planting tomatoes in the same location year after year. Destroy infected plants because research shows that the virus can live in dead plants for up to 50 years.

Anthracnose

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Symptoms: A serious disease, anthracnose can be identified by small lesions, sunken areas, or black spots on the ripe fruit or foliage of the tomato. It can spread quickly and infect an entire patch of tomatoes.

Cause: Anthracnose can be found in the soil, seeds, weeds, and infected plant debris. It’s most common in warm, humid climates and is spread by rain and irrigation that splashes on the foliage.

Solutions: Once infected, plants should be removed completely from the garden. Mulch plants to keep the foliage dry and keep your garden as weed free as possible. Do not use overhead sprinklers, and rotate crops every few years to prevent the disease from infecting the soil.

Wilt

Symptoms: There are two major types of tomato wilt: fusarium and verticillium. Both are fungal diseases that cause the foliage of the plants to wilt, turn yellow, and die. Sometimes the plants survive but remain stunted and deformed.

Causes: Both diseases are caused by a fungus that enters the plant through the roots and then blocks the water supply to the leaves.

Solutions: Rotate tomato plants to another section of the garden if either one of these diseases strike. It takes 4-6 years for the fungi to disappear from the soil. Keep garden beds as weed-free as possible, and fertilize to promote healthy, vigorous tomato plants. Most important, plant disease-resistant varieties. Select varieties with an F (for fusarium) and/or a V (for verticillium) after their names.

Blight

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Symptoms: There are three major blights that attack tomatoes: early blight, late blight, and septoria leaf spot. All three are fungal diseases that result in spotted leaves or wilted leaves. Early blight appears on lower leaves after a heavy fruit set. Spots on the foliage are dark brown to black with a yellow bull’s-eye. They eventually fall off the plant. Late blight happens when the weather is warm during the day but cool at night. Spots on the leaves are dark green to black. The fruits also might develop spots. Septoria leaf spot appears on the lower leaves of the plant after the first fruits appear. The foliage eventually drops off the plant, leaving the fruit exposed to sunscald.

Causes: All three diseases are spread by spores that splash on the plants’ foliage during rainy or wet weather.

Solutions: These diseases spread rapidly and are hard to control once the plants are infected. To keep plants healthy, rotate tomato crops every few years so spores don’t build up in the soil. Also, mulch your plants to keep soil from splashing on the leaves during downpours. To irrigate, use a soaker hose or drip irrigation placed underneath the mulch. It also helps to plant disease-resistant varieties.

Weed Control in Gardens

  • By Doug Jimerson

Blossom-End Rot and Calcium Nutrition of Pepper and Tomato

Circular 938 View PDF picture_as_pdf

Originally prepared by Joshua L. Mayfield and William Terry Kelley
Reviewed by Bob Westerfield

  • Introduction
  • Diagnosis Guide
  • Summary
  • Further Reading

Introduction

Had the ancient Roman Empire not developed concrete and cement, the domed buildings, arched bridges and aqueducts we see today would not still give testimony to the Romans’ ingenuity or to the durability of a simple mineral: limestone. Although calcium (Ca) is well known as the main ingredient in limestone, it has also been used for building strong plant cell walls since long before man discovered its uses for lasting architecture.

Calcium serves several functions in plants, including cation-anion balance, transport processes of cell membranes and assisting with extension of primary root systems. For vegetable producers, calcium’s most important function during the crop fruiting stage is its role in cell wall/cell membrane stability. If Ca is deficient in developing fruits, an irreversible condition known as blossom-end rot (BER) will develop. Blossom-end rot occurs when cell wall calcium “concrete” is deficient during early fruit development, and results in cell wall membrane collapse and the appearance of dark, sunken pits at the blossom end of fruit. Many farmers and gardeners may treat this condition as a fruit disease; however, nutrient and water management regimes are the culprit. The purpose of this publication is to introduce the problem of BER and provide a guide to effectively diagnose and treat this problem.

Diagnosis Guide

Although no data exists to quantify how much annual economic impact blossom-end rot has on Georgia’s bell pepper and tomato industries, it is safe to say that significant loss of fruit occurs during the spring crop season, especially during hot, dry years. What is also unknown in the vegetable research realm is if a single cause leads to BER, or if (as past research indicates) multiple factors contribute to its occurrence. One fact that everyone can agree on is that when BER is first noticed in the field, prompt action is essential to halt further incidence. Four simple questions in the field will lead to a timely diagnosis and treatment of the problem:

Question 1. Is the problem disease- or nutrient-related?

Figure 1. Buckeye rot of tomato caused by Phytophthora. (Photo by D. Langston, UGA)

There are only a few common fruit disorders resembling BER that can lead to an incorrect diagnosis of the problem. Fruit anthracnose may occur on pepper and tomato fruit, but only on the side walls. The same is true for sunscald, which appears on pepper fruit sidewalls and is pale in color. Buckeye rot, caused by Phytophthora, and cucumber mosaic virus (CMV) also resemble BER, but these disorders occur more infrequently than anthracnose. Blossom-end rot is uniformly dark brown and black in color, and appears ONLY on either the lower fruit sidewall or the blossom end of smaller and developing fruit. Often, symptoms will occur as far as 1/3 to halfway up the fruit, but will NEVER start at the stem (calyx) end. Also, BER symptoms will tend to appear during the first fruit set as, early on, growers are unaware of the problem until it’s too late. If these symptoms all correspond, the fruit has BER.

Recommendation: If these conditions all hold true, proceed to Question #2.

2. Is calcium fertilization adequate?

Examine liming and gypsum application records, along with the current season’s pre-plant soil test reports. If pre-plant soil test Ca levels are in the medium (801 to 1,200 lbs. Ca/acre) or high range (>1,200 lbs. Ca/acre), it is assumed that soil Ca levels are sufficient for crop growth. This is even more true for soil pH ≥ 6.0, with supplemental gypsum or lime being applied pre-plant at levels of 500 to 1,000 lbs./acre or higher.

Recommendation: If these conditions exist, proceed to Question #3.

Equally important to soil test results is plant tissue analysis. For bell pepper, sufficient leaf tissue percent Ca content just prior to (or at) early bloom stage should be within the range of 1.0 to 2.5 percent. For tomatoes, percent Ca content prior to (or at) early bloom should be within the range of 1.25 to 3.20 percent. Tissue levels below these would point to a possible emerging Ca deficiency.

Recommendation: No specific recommendations exist for alleviating a low soil Ca level after planting. However, calcium nitrate (CaNO3) is a water soluble source of Ca and nitrogen (N) and is routinely injected in drip irrigation systems. Some research has begun on a relatively new material, calcium thiosulfate (CaS2O3), which also is available for drip injection systems. Injections of soluble Ca sources should begin at bloom and proceed until fruit is approximately golf ball-sized. This is believed to be the critical time when calcium must move into developing fruit to avoid onset of BER.

Figure 2. Blossom-end rot of tomato. (Photo by Joshua Mayfield)Figure 3. Severe BER symptoms progress from the blossom to the stem (calyx) end of the fruit.
(Photo by Joshua Mayfield)

Although some people believe foliar sprays can correct Ca deficiency in developing fruits, research is very inconclusive on this issue. What is well known is that Ca only moves in the plant via the xylem and moves with the transpirational water flow from the roots, up the plant and into developing leaves. Calcium has no ability to flow from the leaves via the phloem to the developing fruit. In addition, once fruit has grown to golf ball size, the waxy outer layer has developed and is believed to be quite impermeable to water. Therefore, it is recommended that all Ca supplied to fruiting vegetables be applied via the irrigation water so as to maximize uptake by roots.

Recommendation: If liquid fertilizers are already being used, proceed to Question #3.

Question 3. Is nitrogen and potassium fertilization excessive?

Research has shown that Ca in soil solution competes with potassium (K), magnesium (Mg) and ammonium-nitrogen (NH4-N) for uptake in the plant. Although no established guidelines exist to determine what proportions of these nutrients in soil or plant tissue are appropriate, it is known that excessive shoot growth resulting from overfertilization of N and K during early bloom and fruiting stages is a major contributor to BER in developing fruit. Since Ca moves with the transpirational water flow, water is going to go to areas of new shoot growth that have the greatest transpirational demand. Calcium will therefore be deposited in the new shoot and leaf tissues that result from excess fertilization, and little will end up in developing fruit where it is needed most. At early bloom stage for bell pepper and tomato, leaf N and K analysis should both be within 4.0 to 6.0 percent. Levels higher than these may indicate excess fertilizer.

Recommendation: Cut rates of N and K if excessive top growth is occurring. Switch N source to CaNO3 or begin injections of CaS2O3 at bloom stage. If these steps are already being implemented, proceed to Question #4.

Figure 4. Sunscald (or sunburn) on pepper with BER-like symptoms.
(Photo by Joshua Mayfield)Figure 5. Pepper Anthracnose with BER-like symptoms.
(Photo by D. Langston, UGA)

Question 4. Is irrigation adequate?

Some people believe the relative humidity and transpirational rates of tomato and pepper during the spring season are the real keys to understanding what factors trigger BER in fruiting vegetables. Fluctuations of soil moisture, as happens during a week of off-and-on rain, may trigger BER due to irregular transpiration rates, affecting the quantities and timing of water and Ca moving up the xylem. Conversely, during hot, dry weather when transpiration is occurring at a much faster rate, developing vegetative parts such as growing leaves and stems become greater sinks for Ca than developing fruits. Lastly, as the waxy outer layer of a tomato or pepper fruit develops, the fruit’s transpiration rate decreases because water movement through the epidermal cells and evaporation into the outside air become difficult. The resulting decrease of Ca that flows into those young fruit tissues via xylem transport is believed to contribute to the onset of BER.

Recommendation: Some research findings have quantified a decrease of BER incidence with increased irrigation rates. However, no recommendations exist for determining the critical moisture levels required in soils to minimize this disorder, nor is information available regarding the severity of moisture deficits triggering BER.

Figure 6. Blossom-end rot of bell pepper.
(Photos by E. Maynard, Purdue University)Figure 7. Blossom-end rot of jalapeno pepper.

For now, the “feel” method is still the most tried and true method of assessing soil moisture in the field. Along the row and out to the shoulders of the bed, the soil should be moist enough to form a ball in your hand and not break apart. The optimal time to increase irrigation and ensure that adequate moisture is being supplied is from first bloom set through fruit development. If BER initiates in fruit, it is believed to be during this early stage of development.

Certain occasions exist where farmers run irrigation pumps “round the clock” and soil still will not form and hold a good ball shape. This may indicate that irrigation demand during the fruiting period is greater than that for which the pumping system was designed.

Summary

It is believed that both nutritional and environmental factors need to be considered when diagnosing BER and recommending treatments. First, a correct diagnosis must be made to avoid recommending costly fungicide sprays when none are needed. Next, a careful examination of a grower’s soil test and leaf analysis records, in addition to their irrigation management practices, will help determine if additional Ca alone or in combination with increased irrigation scheduling will solve the problem. Equipped with a basic knowledge of plant growth, fruit development and Ca movement in soils and plant xylem tissue, growers will have the tools necessary for diagnosing and correcting the adverse effects of blossom-end rot.

Further Reading

Hansen, M.A. 2000. Blossom end rot of tomato. Publication 450-703W. Virginia Cooperative Extension Plant Disease Factsheets, Virginia Polytechnic Institute and State University, Blacksburg, VA.

Taylor, M.D. and S.J. Locascio. 2004. Blossom-end rot: A calcium deficiency. J. Plant Nutr. 27(1):123-139.

Wui, M. and T. Takano. 1995. Effect of calyx removal and air flow or bagging of the fruits during the fruiting stage on the incidence of blossom-end rot in tomatoes, Lycopersicon esculentum L. Env. Control in Biology 33(1):15-21.

Status and Revision History
Published on Mar 27, 2009
Published with Full Review on Mar 30, 2012
Published with Full Review on Apr 06, 2015

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