What have I done wrong with these tomatoes?

[happytodayhappytomorrow]

I’ve grown tomatoes this year, for the first time.
I’ve treated the four plants equally but these are the current tomatoes on one of the plants.

What have I done wrong?

TIA

Possibly nothing.

That's not blossom end rot (caused by calcium deficiency) because it's at the wrong end. It may be bad luck and a cold wet August (depending on where you are in the country. I believe some parts of the country have had something approximating to a summer).

Thank you for replying
We’ve had lovely weather. Could it be overwatering?

It’s splitting due to inconsistent watering. The weather hasn’t helped they have dried out too much on hot days and been too wer on cooler days.
They’ll be fine to eat, I’d pick them and ripen in doors, it might help.

Thank you
It’s only on the one plant which is a bit random isn’t it?

As previous poster said inconsistent watering, the fruit will split if the plant gets too dry, still fine to eat

I have had this this year from the blinking rain then drought. I have found that split ones need to be picked and brought in to ripen, otherwise the woodlice eat them
Never thought of woodlice as a pest before now, but they're little buggers for split tomatoes.

Thank you very much for the replies. I shall pick more tomorrow. I ate some today and they were still tasty

It doesn't look like splitting to me, it looks like an area of rot with the split round the circumference. Splitting from inconsistent watering gives splits running from top to base.

Why does that happen then? Because this is what I have and I assumed it was caused by water - is it something else @MereDintofPandiculation (desperately hopes there's a solution...)

With the cold weather coming, is it time to take all my green tomatoes off the vine and start ripening indoors, or do you think I have some time left? Am in London.

Temperature dropping too low at night can cause tomatoes to split.

@MishyJDI I've picked all my green tomatoes off now and I'm just outside London. Will still ripen and better than wasting them.

@MostDefinitelyNot

Temperature dropping too low at night can cause tomatoes to split.

@MishyJDI I've picked all my green tomatoes off now and I'm just outside London. Will still ripen and better than wasting them.

Thanks! Yes was thinking this may be the time. Today was a good day, but with the weather changing I think Ill bring them all in.

I have't a clue what's happening to OPs tomatoes apart from it not being splitting from underwatering or blossom end rot.

I'm leaving my tomatoes on the vine (Yorkshire) but they're in a greenhouse. I'm going to start keeping the greenhouse door shut, and if it gets much colder, I'll start bringing them in once one tomato on the truss starts to colour.

Some of tomatoes split the same way as the OP’s and it’s definitely what happens when we get a sudden big rainfall in september. Am in the med region so summer is always hot and dry and the skins get a bit tough, then when the rain comes they split.

Which direction they split in seems dependent on variety for us.

In London here and mine are still ripening at the rate that we have enough for lunch each day.

MereDintofPandiculation, my tomatoes must have read your comment.
Look at today’s harvest! Side splitting, top to bottom, now.
They are still very tasty though

Inconsistent watering

Trouble with outdoor toms - lack of watering control. I need to make them umbrellas