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Blossom End Rot

I'm sure I'm not alone when I say that my tomatoes have been afflicted with blossom end rot.

This is probably the 3rd or so season I have dealt with it.

Usually, the first fruits have it and then subsequent fruits don't have it.

I'm just wondering the following things:

1. What causes it?

2. How do you treat it?

If this topic has been delved into before, just point me in the right direction, otherwise it can't hurt to have a good discussion on it here at Homegrown! :)

Thanks all!

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Replies to This Discussion

Permalink Reply by Cornelia on July 27, 2011 at 11:08am

I received some excellent advice about blossom end rot last season and have invested in high P and K organic tomato fertilizer. I lost a few blossoms earlier this month because I was traveling, but the color and condition of the plants seems to be on the upswing. Curious to hear what others have to say, too!

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Permalink Reply by Melanie Baltzer on July 27, 2011 at 1:57pm

Blossom end-rot is actually caused by a calcium deficiency. To combat this, add some DOLOMITIC lime to your water when you water your tomatoes. Some people say eggs shells due tot he calcium contained in them, but it is not enough. The lime trich will work. How much to add? I don't have any specific amounts in mind, when I did it before I just added an handful or so and stirred it around well.

Hope that helps!

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Permalink Reply by Shira Friedman on July 27, 2011 at 2:02pm

Calcium deficiency is correct - lime is a good remedy.

Frequent causes are, uneven watering, over fertilizing (too much salt in the soil) or overusing manure (too much amonia).

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Permalink Reply by Lizz on July 27, 2011 at 2:40pm

can this apply to squash?

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Permalink Reply by Matt Kochka on July 27, 2011 at 3:00pm

Lizz said:

can this apply to squash?

Yep, sure does!

Don't forget, there are more reasons than lack of soil calcium that can reduce calcium uptake. Insufficient watering, improper pH, imbalanced nutrition in general, or root health issues could hinder calcium assimilation.

With this being said, blossom end rot is usually caused by low calcium in the soil and you should start there. (a soil test can help avoid the guessing game)

Isn't great to learn that it is not bacterial or fungal and you don't have to worry about spreading it?

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Permalink Reply by Janine Roe on July 29, 2011 at 9:40pm

thanks all for the replies. Very helpful. I will give the dolomitic lime a try. Would I apply it each time I water or just once in a while? Would I apply it in the beginning of the season only or throughout?

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Permalink Reply by Omega Farms on July 31, 2011 at 8:52pm

How often does the dolomitic lime need to be applied? I worked some into my soil when I prepared the bed for planting & still got end rot. Maybe I didn't use enough?

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Permalink Reply by luv2gardengirl on August 13, 2011 at 10:42am

I also battled this with my tomatoes. I grow them in Grow Boxes which are wonderful!! but the 1st few tomatoes also had that. however, since then it has not affected any more of them?

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Permalink Reply by Ray T. Goss II on November 2, 2011 at 3:27am

I use a Planters II mineral mix with a product called Thrive for a good tomato myco source from the start with my young seedlings when I shift them from a 72 cell flat to bigger containers before transplanting outdoors. I do the same thing when I transplant them outdoors. I apply the Planters II minerals once per month thereafter. I apply the Thrive two more times through the growing season.

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Permalink Reply by HOMEGROWN.org on December 1, 2011 at 1:45pm

test

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Permalink Reply by Lucy Goodman on December 15, 2011 at 6:45am

too late for 2011 but just in time for 2012.

BER usually is caused by the lack of calcium availability in your soil. many people will put a TBL of epsom salts into each planting hole to correct this as this usually will allow calcium (if you have enough in your soil) to be released. But if you have too much magnesium in your soil this will not work and they only way to know what is in your soil is by getting a good soil test that tests for more than NPK and pH.

Soil testing is not hard to do nor is it expensive at around $20 per test per year (and most home gardeners need only one test as you grow on under an acre, if you have many acres than usually one test per 2 to 3 acres is sufficient) and it tells you a lot about your soil and with that knowledge you can get together a plan to improve your soils

All that said some maters get BER a lot more easily than others. For example I find Opalka canning tomatoes get BER a lot more than Amish Past canning maters. So variety selection is also important.

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Permalink Reply by Ginny Hopper on December 15, 2011 at 11:57am

I have discovered through other resources that this problem in squash is also caused at the time of flower blooming. You have a male bloom and a female bloom and if they do not bloom and pollinate at the correct time of bloom, the squash will grow but rot at the ends, it is a non-pollinated growth.