tomato health check: blossom end rot, anyone?

blossom end rotACCORDING TO MY AUGUST 1, 2010 scientific Facebook focus group (kidding, but four-dozen people did reply to my question about how their plants were doing) it was generally a thumb’s-up tomato year then so far.  But with multiple hot, dry spells locally (even though I had been watering!), I kept worrying about the dreaded blossom end rot. And there it came, as expected—though hopefully not to stay.

Blossom end rot, which (just as it sounds) is a rotting of the fruit that begins as a watery spot on the blossom end, also affects peppers and eggplants. It’s a physiologic disorder—not something caused by a virus or fungus or bacteria, like so many other tomato ailments, but rather by physical stressors that prevent the fruit from taking up enough Calcium to come to ripeness in prime condition.

The watery spot transitions to a dry, sunken lesion (it looks as good as it sounds, above, served up on a non-silver spoon).

Why the deficiency of Calcium, though? What did I do wrong? Various factors can bring it about, including soil that suddenly goes dry (as in a fierce heatwave), excessive fluctuations in soil moisture, over-application of high-Nitrogen fertilizers (not guilty!), root-system damage, or the excess of other soil salts, among other causes.

On August 2, 2010, I didn’t see many more affected fruit—yet.

Like many of my Facebook friends (join us there?) from the Finger Lakes to Tucson, Michigan to Massachusetts, at that time, I did see this, though: generally late ripening. I was just then starting to get my first tomatoes, despite all the heat (which actually can slow down fruit set, as counter-intuitive as that may seem with a heat-loving crop).

And so I waited for enough fruits for that thrilling first pot of sauce. What about you? What’s the view into your slice of tomato life?

(Want more tomato dish? All my tomato posts–wisdom, whimsy and even recipes–are collected here.)

  1. lou desena says:

    hi–the only “problem” that i had with tomatoes this year was a “leaf-curl” on
    about 8 plants.i ripped out the plants and discarded them in the “garbage”.i
    did not want last years “disaster” to repeat this season.otherwise the only other
    thing is that the plants are “bushier” and lower.usually they reach the top of the 4
    foot stakes.the tomatoes are turning red “slower”,but they are coming-a few
    each day.
    lou desena-ct

  2. Eleanor says:

    My tomatoes (in Concord, New Hampshire) are doing beautifully this year, with extra watering to get them through the recent drought and heat. I just heard that late blight has started here in northern Vermont, where I’m on vacation; haven’t heard of it hitting New Hampshire yet. No blossom end rot for me yet. I’m having a lucky year in the garden!

  3. Dee says:

    My Tomatoes ( Herriman Ut) are doing much better. I started to see the blossom end rot on my tomatoes and I put a cup of milk with a gallon of water and feed this to my plants and it seems to be gone. I also sprayed yield booster on my tomatoes and they seem to be doing much better.

    1. Margaret says:

      Welcome, Dee. Are your tomatoes posing for the next “Got Milk?” magazine ad campaign? :) Love this news; thank you. See you soon again.

  4. diana says:

    I decided to plant heirlooms, and it has been a crying shame. Very little acutal tomatoes and lots of BER. WIll try the milk idea, maybe not too late to save some.

    1. Margaret says:

      Welcome, Diana. I tested grafting my heirlooms onto sturdier rootstock as an experiment to try to get heirloom fruit this year. You can read about it here. I only did a few – but it seems to have helped!

  5. suzanne says:

    No ber but have wild squirrel problem . Never have we had them eating our tomatoes especially the sungolds. Any ideas besides traps to get rid of them?

  6. Laura says:

    Laura in Vermont here. Last year, when I experienced some BER on my zucchinis, I discovered (somewhere!) a mixture of epsom salts and powdered milk that seemed to take care of the problem. This year as my tomatoes and zukes were blossoming I applied the same. No BER at all! Is there a scientific reason for this or is it just my Botanical Faith?

    1. Margaret says:

      Welcome, Laura. I love all these home remedies — I used to have books full of them and old clippings, etc., of articles containing them from vintage Organic Gardening and Harrowsmith magazines and so on. I don’t usually see them on cooperative extension sites, but more as conventional wisdoms/real people’s tactics on other websites. The milk is supposedly because of the calcium…the epsom salts (containing magnesium) would I think help in the uptake of calcium. I am no scientist, but I do know that excess or deficiency of various elements like this can affect the uptake of another, and I believe one of magnesium’s properties is to aid in calcium uptake by plants.

  7. Eileen says:

    I had problems with my Striped Romas last year, but I’m not sure if it was blossom end rot or what. They were sausage shaped tomatoes with a pointy tip, and the tips just kind of went brown and dry. I felt like I couldn’t sell them at the market because they were ugly, but the tomatoes themselves were absolutely beautiful and meaty – they made great pico de gallo!

  8. Marty says:

    I haven’t had an issue with BER since I started adding egg shells when I transplant my tomatos. I rinse the shells (so they don’t start to smell), crush them (to save space) and store them in a mason jar all year long. When it is time to plant the tomatos I sprinkle 2-3 tablespoons of crushed egg shell into the hole before adding the transplant. The shells are high in calcium, organic, and very close to the roots.

  9. Eileen says:

    I will try the eggshells (and maybe ag lime?) for calcium, but I’ve heard that it’s not calcium and that’s a common misconception. Don’t know what to believe.

    1. Margaret says:

      Hi, Eileen. I found a fact sheet from North Carolina State that explains the use of lime etc. to improve Ca levels in the soil (which must be done well in advance to help, not an instant fix)…but this is a physiological disease that often occurs when Ca can’t get up into the fruit in sufficient amounts after a stressor like a dryspell/uneven watering. So I think it’s sometimes that there isn’t enough Ca available, and other times that stressors (drought) prevent the uptake, even when it’s in the soil — or so I have always thought was the case.

  10. Eileen says:

    Thanks for the link, Margaret. I’ve got to test my soil – I’ve been lazy about it. I’ve got ag lime, but you’re right – it’ll take a while for it to actually help. I wonder if the egg shells will be quicker about getting the calcium into the soil…

  11. Matthew says:

    So far only on the Romas. I crumbled up some egg shells and worked them in around all the nearby plants. Since then, so far so good. Next year I’m using Marty’s method.

  12. Sharon says:

    Aargh, got this problem this year for the first time in all my years of growing tomatoes. I’ve only ever had the issue of split tomatoes.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.