Thoughts of Blossom End Rot

I have read the literature on BER and understand what is said about water, calcium uptake, etc. Supposedly, fluctuating moisture levels are the main culprit. However, to paraphrase the great Cornell U. horticultarist L. H. Bailey, "find what is successful for YOUR soil and YOUR climate." BER used to be an early season problem for me, but anymore it is rare. As I plant my tomatoes, I work in 2 or 3 tablespoons of capsulated limestone pellets (30% calcium carbonate) in each hole. Its simple, its inexpensive, and it works for me.
U of MO soil tests show that my soil is not deficient in calcium. Rainfall is often heavy (2-5 inches at a time) up to the middle of June, and my garden does not drain well. I usually plant May 7-15 in 50 foot raised rows (not raised beds). Straw mulch is applied and soaker hoses are used during dry periods.

I garden in North Central Missouri

If your soil is not deficient in CA++ there's no need to add it.

There are many variables that can cause BER to develop, not just too much moisture, but too dry, too hot, too cold, too windy , growing in too rich soil or using too much fertilizer is also a stress to the plants and when the plants are stressed they are susceptible to BER.

Uptake of Ca++ from soils that have sufficient CA++ goes OK, but those stresses to the plant lead to maldistribution within the plant such that CA++ doesn't get to the blossom end of the fruits. There's also internal BER where you cut open the fruits and it's black inside but no exterior indication of BER.

Studies have been done that show that when plant tissues are assayed for Ca++ they are fine as long as the soil Ca++ level is fine, but BER fruits were found on those same plants indicating the maldistribution within the plant.

There's only two situations, well really just one, where CA++ needs to be added. One is if the soil or planting mix has NO CA++ and the other is if the plants are growing in too acidic soil, which binds CA++ in the soil and then that problem is solved, not by adding CA++ , but by altering the pH of the soil.

Hope that helps.

Carolyn, who had the pleasure of many times visiting the Baily Horticultural building when she was an undergrad at Cornell. Delighted to see him being quoted.

Thanks, Carolyn, and mgsid too for the quote.

Bottom line for me...BER happens. Sometimes with the best of efforts. I had it happen last year with one tomato on one plant. Didn't have a single incident again. Other years have had similar...maybe on a few tomatoes on one plant but not the whole crop. My usual situation has been similar to mgsid's...usually happens with the earliest of the tomatoes. Maybe that's when I'm the most diligent about fertilizer, etc and they are stressed as Carolyn points out. But it's also when the temps, rain, and other weather factors vary a lot in the early season.

Actually, I worry more about fungus and bugs more than I worry about BER.

BER is temporary. Fungus and pests are forever! Lol.

20 yrs ago, when I lived in SoCal I thought gardening was sooo easy, then I moved to Texas.

Carolyn, I appreciate your comments on blossom end rot. The 2 gardens where I plant tomatoes were previously in sod. The pH in both are on the acidic side (5.5-5.9) as near as I can remember without digging up the lab reports. So adding calcium at the time of planting seems to be helpful in my situation.

Your info on fertilizer and too rich soil will be helpful when I get BER questions from other gardeners. Part of my duties as a "master gardener" is to provide advice, but the more I learn, the more I realize how much I do not know!!!

1lisac--I say "amen" to your comment. I read everything in the tomatoes forum and always enjoy your insights.

MGsid, I don't see 5.5 to 5.9 as being that acidic and it's good to remember that pH is on a log scale.

Tomatoes grow just fine at a pH of about 5 to close to 7.

If the report you got back didn't suggest altering the pH then I guess thay didn't think it was that acidic either. ( smile)

Carolyn