A Gardeners Forum Forums Gardening Reference Gardening in 2006 blossom rot

Is blossom rot caused from to much water or not enough water? I live in California, between Sacramento & Lake Tahoe. We have just gone through a 12 day heat wave. Temps as high as 110. I water at least every other day for approx. 1-2 hrs. (one day I went to the river and forgot to turn off the water for 5 hrs. I didn't notice if I had it before that or not. The other thing (and suspect it's the heat) but I'm not getting any production from my cherry tomatoes plant (sweet 100); every other year this has been a mighty producer. Your help is appreciated.

The short answer is both. The intense heat is the most likely culprit for the decreased fruit set.

BER is a symptom of not enough calcium in the soil.
I have had good results the last three years keeping it away by adding lime to the soil(Tomatoes like acid soil so go light with it).

The garden centers have a treatment for BER. It's a high calcium solution you water the plant with.

I usually do add lime but this year I didn't. I've had trouble in the past. I always thought it was from inconsistent watering. I have always been under the assumption that tomatoe plants like to dry out slightly between waterings. Is that correct?

It is inconsistant watering. It really has very little to do at all with calcium in the soil.

That is correct ellie. That's correct about most plants.

I'm not so sure about the over watering. I have received 20" rain in June and July and no BER problems. Two summers ago was just as abnormally wet and it was never a problem.

I usually water every other day when the temps are over 95 for about 1 hr to 1 1/2 hrs. I have a drip system with 5 gal per hr. drippers on each. Do you think that's to much? What's interesting is just some of the fruit gets the rot. I'd really like to get this watering thing down right. I can use all the help I can get.

I decided to try drip irrigation for some of my crops this year. Turned out we have received 20" rain the last two months and I have used my drip lines a total of once on my pumpkins and watermellons. Unbelievable.

I haven't had to water much here in Western New York either.. lot's of rain in our neck of the woods too...

We've got some post above about tomatoes too,
and I believe it's a combo of both...

When one doesn't water consistantly, once too much, 4 or 5 days with hot and dry then you water for one hour, then two days later it rains, and it's soooooo hard to prodict the weather..

But one of the reasons' it does have something to do with the nutrients in the soil is, when ther'es hot and dry or shallow watering *not deep root watering* the plant puts out roots very close to the upper level of soil in your garden.. *it may have a huge root system when you pull it up, but it's all up towards the top of the soil* where water would have been with quick, or shallow or frequent quick waterings..

and when that top soil area dries out, the roots, tend to shrivel up and can't deliver nutrients to the plant "Consistantly" because those roots that dried up, dry up and then the plant has to send out new or different direction roots, and can eventually feed it'self again..
So that's a part of it, roots drying up and not delivering key nutrients the plant needs...

I have experimented this year with not watering at all, (only when I initially planted)
*of course we've had rain too*
so, I will continue to experiment in the years to come** with not watering frequently and letting the tomato plant dig it's roots in deep...
to find the needed water..
and see how it goes..

Additional comments.

There's a lot reasons for blossom-end-rot; all of them can be traced from the plant's inability to utilize calcium in the soil. The Calcium in the soil becomes available to the plant only when the soil is evenly moist, therefore, the most common causes of the BER are drought and extreme variation in soil moisture,i.e., going from completely soaked to very dry and back again. These variations maybe from the weather or from watering practices or both. Of course, Calcium deficiency may include mineral imbalance, root damage, temperature swings and/or high salt content of the soil.

Mulching will help maintain soil moisture. Regular but not deep waterings are better than frequent light waterings. However, do not let plants to dry out completely. Avoid using high nitrogen fertilizers or fresh manure. Manure, especially with high salt content should be partially decomposed before being used.

Thank you all for your advice. I assume I've been deep watering since I let it go 1-2 hrs. Are you suggesting I only water maybe 45 mins. every other day (if the temps are to high) and I would assume if the temps get high again, say over 90 I should water every day for 45 mins.??? I really appreciate the responses I get. I read everyone's postings and find it very informative. Thanks again.

My personal opinion is that you can never water perfectly so I use a BER spray maybe every other week or so. I use it on tomatoes, zucchini and peppers as needed. If I screw up watering or not watering I spray right away.

Um..... confused and so here comes a question.
Blossom END rot?
Wouldn't the blossom end be the stem (top part) of the tomato, the area that is begun in the flower?
I have read alot of the posts about BER, but didn't know what it was, and now my neighbor's tomatoes have it.
I saw it for the first time on her beefsteaks.
The lower third of the tomato is brown.
She said she got calcium and that solved the problem.
Anyway, I really am confused as to the blossom end thing.
Somebody educate me, please !

Deb, haven't you ever picked off those dead blossoms off the end of tiny new tomatoes(err...julianna-itis)?

Knock on wood I have never had BER...But I water daily unless there is rain. I leave my overhead sprinkle on for 1-1 1/2 hours and I water when you really are not suppose to in the evening. My plants get about a half an inch of water daily.

Oh ! Thanks, John, now I get it.
Yep, I pull those brown petals off too just for the heck of it.
OK, actually because I can't wait to see the new baby tomato beneath it !