can anyone please tell me why some of my tomatoes blooms are falling off? my mr. stripey tomato plants are blooming but then the stem turns yellow and falls off some of my other tomato plants have tomatoes but a few of the blooms on them do the same thing. also a few of the tomatoes on one got about the size of a golf ball and started rotting at the blossom end. is this what is called blossom end rot? what do you do about that? thanks.

The blossom end is the bottom. There is a spray you can get that may help some. The crushed egg shells are said to work well, but they will act slowly, no quick fix.
Right now the temps in Oklahoma are not good for tomato production. Blossom drop is common in this heat, and even some fruit drop of the smaller fruits. Are the main stems turning yellow, or the fruit stems? If main stems are turning yellow, you could be watering too much, but you'd probably also see leaves yellowing and falling off. Blossom end rot is actually caused by watering stress, too much and then too little, but the calcium in egg shells and from other sources helps the plant deal with these stresses, but are best added to the soil at planting time or earlier. Some folks suggest using Epsom Salts to help with BER, but the evidence for that is sketchy at best. Might be worth a try, though.

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Dave
Even my growlights are getting restless!

yes the fruit stems are turning yellow and so are some of the leaves but i just watered them yesterday i haven't watered them since the storm we had a couple weeks or so ago. i thought they needed watered because my squash had some little ones that are hollow and orange not yellow. some of my beans are also turning yellow. the leaves on my tomato plants are curled up and turning brown. a week ago they all looked really good but i fertilized them don't know if that could be the problem though? everything else looks ok.

i just watered them yesterday i haven't watered them since the storm we had a couple weeks or so ago.
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They will need watering more regularly if the heat is extreme, at least weekly, even if you get a storm as most storm water is lost thru runoff but when you do water, soak the soil deeply. Mulching will help.
Some shadecloth scraps over the plants may help prevent heat stress too.

Blossom end rot is usually from a calcium deficiency and it can also come from moisture stress. If both of these factors are present, even if there is calcium available to the plant, it can be carried to the leaves where the moisture is transpired out, leaving none for the growing fruit. Calcium can be supplied by a side dressing of dolomite but it's slow acting and should be applied at the soil preparation stage.

There are liquid forms of calcium available, but they won't correct the damaged fruit, only the developing ones. Seaweed extract has a good calcium content and it would help the plant to overcome the stress also.

Excessive nitrogen can also increase the severity of blossom end rot, so lay off the high nitrogen ferts. Something like 5:10:10 would be more suitable but not until the plants have retained their vigour.

Your plants sound as though they are in a state of extreme stress, so mulch heavily after a thorough, deep watering, apply some seaweed extract to the rootzone, remove all affected fruit, cover with some shade on extreme days and they should recover OK. If there is calcium already in the soil, they'll take it up once the roots develop a little and the moisture levels have remained constant for some time.

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The secret is the soil.

John...This is very intriguing. I have heard so many "authorities" say that calcium can reduce the stresses of over/underwatering, or that calcium deficiency itself is the primary cause of BER. I had a fair amount of BER last year after a very wet and warm period during early summer. The literature usually refers only to "watering stress," overwatering followed by underwatering, or vice/versa. I'm finding that there is no general concensus on this issue, and the most controversial issue I've seen so far is the idea that Epsom Salts can reduce BER. I find it very difficult to sort out conventional wisdom from scientific data. I've relied on the Rodale Press and related information for years, and no longer know whether it's a reliable resource.

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Dave
Even my growlights are getting restless!

Thanks, Longy. I read several of those articles, and they confirm what I have always heard.

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Dave
Even my growlights are getting restless!

I can confirm just about anything anyone says with a simple google search. It is the simple yet profound proliferation of misinformation on the internet that prepetuates misconceptions like this. Read the recent university research on the topic and you'll see that it is plant stress(including over-fertilizing) of some kind that causes the fruit to lose it's calcium resulting in BER. That plant is not lacking calcium....the fruit loses it. This cannot be remedied by adding some form of calcium(egg shells, limestoine, etc) to the soil. Again, most soils have more than adequate amounts of calcium in it already. Dave, Carolyn gets into this in detail in her book. Check the well-known agricultural university websites for tons of articles relating to plant physiology and biology. BER also mostly shows up early in the season, like it did to you. Epsom salts are magnesium sulfate I believe. Another internet-perpetuated myth.

davida580, sounds like the heat and possibly water-stress is causing your problems. Heat and humidity cause blossom drop and just like everything else, some varieties are more susceptible than others.

Well that's my posting for the day. I gotta get back to the garden!

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John - Zone 6