Hi,

I have been growing some tomato plants in grow bags outside, 3 Alicante and 3 Sweet Millions. They are good strong plants with lots of blooms and nice thick stems. Each plant is about 4.5-5 feet tall.

I have created a water mechanism that consists of 2 x 2ltr drink bottles with the bottoms cut off and a tube stuck into the top of the bottle. I have put the tubes down into the grow bags so this will water the tomato plants directly to the roots. I just fill up the bottles each night and I know I have given the grow bags 4 ltrs of water each night.


Everything looked great up until a few nights ago, I noticed that some of the Alicante newly formed tomatoes have started to produce black bottoms where the bloom was. I am assuming this is Blossom End Rot. The other Alicante plants in the same grow bag looks unaffected and the 3 sweet millions in the other grow back look very healthy.
The questions a

I am over watering the tomato plants? I was under the impression that tomatoes love water when producing fruit.

The soil is certainly moist all the time, as the weather has not been very hot recently. But I have put holes in the bottom of the bags for drainage. I am not getting a huge amount of water loss from the bag when watering.

I also understand that Blossom End Rot is a cause of calcium deficiency. Can I add calcium to the grow bags to prevent the other tomatoes suffering this problem? If so how?

Steve

I have my plants in large pots and sitting in plant pot trays which I keep full of water so in effect the watering is the same as yours, the soil being moist all the time. I have only one tomato with end rot and that oddly is also on an Alicante, so I don't think it's the watering system. I feed mine with a liquid tomato feed every few days.

"Steve Upton" wrote
I have been growing some tomato plants in grow bags outside, 3 Alicante
and 3 Sweet Millions. They are good strong plants with lots of blooms
and nice thick stems. Each plant is about 4.5-5 feet tall.

I have created a water mechanism that consists of 2 x 2ltr drink
bottles with the bottoms cut off and a tube stuck into the top of the
bottle. I have put the tubes down into the grow bags so this will water
the tomato plants directly to the roots. I just fill up the bottles each
night and I know I have given the grow bags 4 ltrs of water each night.



Everything looked great up until a few nights ago, I noticed that some
of the Alicante newly formed tomatoes have started to produce black
bottoms where the bloom was. I am assuming this is Blossom End Rot. The
other Alicante plants in the same grow bag looks unaffected and the 3
sweet millions in the other grow back look very healthy.
The questions a

I am over watering the tomato plants? I was under the impression that
tomatoes love water when producing fruit.

The soil is certainly moist all the time, as the weather has not been
very hot recently. But I have put holes in the bottom of the bags for
drainage. I am not getting a huge amount of water loss from the bag
when watering.

I also understand that Blossom End Rot is a cause of calcium
deficiency. Can I add calcium to the grow bags to prevent the other
tomatoes suffering this problem? If so how?


Causes of Blossom End Rot are dry roots and/or acidic soil.

If your growbags are always moist then it must be the pH, worth checking.
If it is the pH then they were not good quality growbags and I would suggest
you don't use the same manufacturers again (and let us all know the
culprit).
The small fruiting varieties of Tom do not seem to suffer this problem.
If you use rainwater to water try using tap water provided it's hard water.

--
Regards
Bob Hobden

"Bob Hobden" wrote

Causes of Blossom End Rot are dry roots and/or acidic soil.

If your growbags are always moist then it must be the pH, worth checking.
If it is the pH then they were not good quality growbags and I would
suggest you don't use the same manufacturers again (and let us all know
the culprit).
The small fruiting varieties of Tom do not seem to suffer this problem.
If you use rainwater to water try using tap water provided it's hard
water.


Forgot to mention, you are using a tomato feed as it says on the bottle?

--
Regards
Bob Hobden

Thanks for the reply,

I think Alicante are quite prone to Blossom End Rot. So perhaps I am panicking about nothing. I have done some research today and I read that you can lose up to 35% of Alicante tomatoes from Blossom End Rot (I cannot remember the website I read this on).

Last year, like many others I suffered a major case of tomato blight and I had to throw 15 tomato plants in the bin. I am hoping this year I do not have the same problem. But unfortunately I have a different problem this year.

I give the tomato plants a good dose of Tomatorite once a week.

Hi,

I use the tomatorite to feed the plants once a week. I think this is as described on the bottle.

The grow bags are actually tomatorite as well, so I thought that these would be ideal, they were thicker than the standard grow bags you can buy. I have not checked the pH, but I will test it and see what it says.

Also, I always use rain water to water the tomato plants. I was worried about the chlorine in tap water damaging the plants. I will try watering with tap water and see if this helps. My area is Cambridge, so we do have hard water. I had been advised in the past from a family member that tomato plants do not like tap water because of the chlorine in it. If you have to use it, then to let it stand for 24 hours before watering them to let the chlorine settle. I am not sure if this is true?

I am a bit of an amateur when it comes to gardening, but I have had success in the past with tomatoes.