I noticed BER on a few tomatoes on 3 of my 26 plants today. Eight of these plants were transplanted into 20 gallon fabric pots with a an amended peat-based potting mix about 6 weeks ago. They are now ~4 feet tall. All three affected plants are in these 20g pots. The rest of my tomato plants are in raised beds or 5G self-irrigating containers (all of which appear just fine so far). This is my first garden. I am in zone 6b.

What I thought was interesting is that the affected tomatoes are all on the second truss. The tomatoes on the first truss are fine as are the ones on the 3rd+ trusses. Not all tomatoes on the 2nd truss are affected either. At least for now. Two of the three affected plants are very vigorous growers (Cuore di Bue and Costoluto Fiorentino); the other is not quite as vigorous, but is growing well (Pineapple). There is only 1 affected tomato on the Cuore di Bue and Pineapple plants and 3 on the Costoluto. At least as far as I can tell, as the BER is currently not that noticeable except on the tomato on the Cuore di Bue plant.

All of my pots were amended with dolomite lime, bone meal and slow release granular fertilizer. I also fertilize with a low dose of soluble fertilizer every 10-14 days. I do not believe there is a lack of calcium in the pots. All pots are mulched with 2-3" of shredded pine bark.

I strongly suspect the BER is due to a watering issue as I hand water the pots.

What I was curious about is, since the BER is only affecting the 2nd truss on the plants, does that suggest that around the time the tomatoes on this truss were developing the watering was too inconsistent? and if I keep to my current routine it should be ok since all the other tomatoes seem fine? I am trying to decide what I need to do if anything.

A few weeks back I switched to watering for 30 seconds per pot from 20 seconds per pot. The 30 seconds is enough to thoroughly soak the potting mix and have some water come out the sides of the fabric pots. I increased primarily due to the current weather having highs between 80 and 90F with little rain. I figured 30 seconds from my sprayer is about 7.5L/2 gallons of water (yes, I experimented to determine this). I have all the pots on large plastic collection trays and sometimes there is a bit of excess water, but that is typically gone within the next few hours. It seems like a lot of water given the 1"/sq.ft recommendation (that is about 10 seconds of water from my sprayer). Currently I water every 2-3 days depending on rain/temps. This week it is every 2 days. I water directly onto the mulch in the evenings.

I am just not sure what I should do. Do I continue with 30 seconds of watering? do I switch to 10 seconds and water every day? am I over watering? am I overreacting (probably yes!)?

There is just too much confusing information for new gardeners. I consistently read/hear "water DEEP" and "less frequent"; while at the same time "water consistently and regularly" to avoid BER. Those contradict each other. People also recommend irrigation systems quite often. Those timed systems must also water every day? so that would not be considered 'deep' watering that so many people suggest. Although, perhaps the 'deep' watering is more for in-ground gardens and less applicable to raised beds and pots?

Appreciate and suggestions/comments. Thanks!

It's definitely an inconsistent watering issue and plum varieties are the most susceptible. I had horrendous problems the year that I grew Costoluto Genovese and it affected more than just the first fruit. None of the other 20+ varieties in the same garden were affected.

I also grow container tomatoes in 3-gallon pots and I find that I need to water them twice a day as they dry out fast, even with mulch on top.

I think the "deep watering" suggestion IS for in-ground plants so that their roots will go down to find the water.

Linda

Tomatoes in containers are what got me started on drip irrigation! Watering all those plants was simply not something I could do once a day, and twice a day is how often they (and eggplants, and other thirsty plants) needed it.

I was out today tweaking the timer for one of the rows of my tomatoes. 3 of the containers are the old EB type, with just 2 gal reservoirs (my homemade ones are 4-4½ gal, or 1½-2, for bucket sized, for single plants), and when it gets very hot, even filling twice a day (for 2 plants) ends up with them beginning to dry out, after 12 hours! So I re-set my timer for that row to every 8 hours, but a little less time, so it won't overflow, but also won't dry out. This will give you an idea of how much water they take in! And it's next to impossible to keep up with it, by hand watering, without them drying out in a SIP, let alone in a regular container.

Labradors wrote: ↑Fri Jul 03, 2020 1:52 pm It's definitely an inconsistent watering issue and plum varieties are the most susceptible. I had horrendous problems the year that I grew Costoluto Genovese and it affected more than just the first fruit. None of the other 20+ varieties in the same garden were affected.

I also grow container tomatoes in 3-gallon pots and I find that I need to water them twice a day as they dry out fast, even with mulch on top.

I think the "deep watering" suggestion IS for in-ground plants so that their roots will go down to find the water.

Linda

I figured as much. Going to move forward with watering every day if it's 90F+ and every other day if in the 80F range; and hope for the best! Trying to not worry too much because gardening is supposed to be relaxing, lol!

pepperhead212 wrote: ↑Fri Jul 03, 2020 7:49 pm Tomatoes in containers are what got me started on drip irrigation! Watering all those plants was simply not something I could do once a day, and twice a day is how often they (and eggplants, and other thirsty plants) needed it.

I was out today tweaking the timer for one of the rows of my tomatoes. 3 of the containers are the old EB type, with just 2 gal reservoirs (my homemade ones are 4-4½ gal, or 1½-2, for bucket sized, for single plants), and when it gets very hot, even filling twice a day (for 2 plants) ends up with them beginning to dry out, after 12 hours! So I re-set my timer for that row to every 8 hours, but a little less time, so it won't overflow, but also won't dry out. This will give you an idea of how much water they take in! And it's next to impossible to keep up with it, by hand watering, without them drying out in a SIP, let alone in a regular container.

That is scary and not comforting at all, lol! I don't think I am quite at that point though. It is certainly hot, but nothing has dried out to that extent so far. I suppose that is one benefit of living in Canada.

Along with inconsistent watering, its also the rapidly growing plant's inability to move available calcium fast enough to the growing fruit end. When the plants slow a bit later in the season, it almost always clears up on it's own. On another note: Texas Tomato Food claims no BER with their product. I don't like claims like that, but ordered some 3 years ago, only because it's a very good fertilizer. Guess what? No BER in 3 years, but can't prove it was the TTF.

edweather wrote: ↑Sat Jul 04, 2020 12:20 pm Along with inconsistent watering, its also the rapidly growing plant's inability to move available calcium fast enough to the growing fruit end. When the plants slow a bit later in the season, it almost always clears up on it's own.

This is what I am hoping. I am just going to continue to water regularly and hope things improve on their own going forward. Not much else one can do. I found BER on 5 different plants now. The worst is the Costoluto, where I pulled off 9 tomatoes so far. The Andean is next at 5. Not really surprised given these varieties seem to be susceptible. Next time I will try growing these ones in the beds instead of pots.

As for amendments/ferts like TTF, I am sure it's good and it probably has a bunch of Calcium in it. I would probably buy it if I saw it here in Canada. Given that BER is not the typically the result of a Calcium deficiency in the soil, I doubt it really prevents BER. They actually state that in their footnote "*Lack of blossom-end rot can't be guaranteed because there are several causes not related to calcium deficiency. However, the amount of calcium and instant availability of it make BER much less likely." Sounds like they add calcium nitrate to it.

Here's an article by the late Dr Carolyn Male. Carolyn was a well known tomato grower and molecular biologist.
She starts out by saying:

Blossom End Rot (BER) is one of the most common tomato problems seen in the early part of the season. It is a physiological condition, not a disease caused by a fungus, a bacterium or a virus. Therefore it cannot be treated. And as I'll explain below, it is very difficult, if not impossible, to prevent.

http://www.webgrower.com/information/carolyn_ber.html

QAGUY wrote: ↑Sun Jul 12, 2020 7:11 pm Here's an article by the late Dr Carolyn Male. Carolyn was a well known tomato grower and molecular biologist.
She starts out by saying:

Blossom End Rot (BER) is one of the most common tomato problems seen in the early part of the season. It is a physiological condition, not a disease caused by a fungus, a bacterium or a virus. Therefore it cannot be treated. And as I'll explain below, it is very difficult, if not impossible, to prevent.

http://www.webgrower.com/information/carolyn_ber.html

Thanks for the link. Good information. I think what happened to me was a combination of genetics (variety) and hot weather. We had a long stretch of hot (90F days) weather where I live in Ontario, Canada with little rain. My best guess is that increased transpiration along with strong growth and inconsistent watering (and being in pots) created problems for some of my varieties - Costoluto Fiorentino, Andes, Cuore di Bue, Pineapple and Black Sea Man. I lost about half of the Costoluto tomatoes and maybe 2 to 5 from the rest, which isn't bad. Weather has calmed down now and we will see what happens going forward.