[Debz]

My mum and I are growing the same varieties of tomatoes but hers are splitting a lot.  They are mostly cherry varieties.  Do you have any clues why that would be?  She thought she was feeding too much so she is actually measuring the feed now and it is still happening.

[Yorkie]

It's more likely to be a watering issue than feeding, I'd have thought.

[savbo]

it's usually about uneven watering isn't it Yorkie? Not enough when they were forming then too much when they're ripening?

[oldcow]

I'm growing three varieties, and I watered all of them every day both when growing and when ripening. The cherry tomatoes (Sungold) split a lot. The ones that didn't split on the vine often split when I picked them up. The Dr Carolyn tomatoes split occasionally, and the Costoluto Fiorentino never did.
So I think that watering patterns do matter, but there are some varieties that are just more prone to it. I suppose that cherry tomatoes, due to their size, need a thin skin otherwise they'll be unpleasant to eat, and so they're more likely to split.

[shokkyy]

I'm growing three varieties, and I watered all of them every day both when growing and when ripening. The cherry tomatoes (Sungold) split a lot. The ones that didn't split on the vine often split when I picked them up. The Dr Carolyn tomatoes split occasionally, and the Costoluto Fiorentino never did.
So I think that watering patterns do matter, but there are some varieties that are just more prone to it. I suppose that cherry tomatoes, due to their size, need a thin skin otherwise they'll be unpleasant to eat, and so they're more likely to split.

Yes, I've had problems with Sungold splitting too. And yet Gartenperle, also a cherry and watered in exactly the same way, haven't been splitting at all. So maybe it's more the variety than anything else.

[Yorkie]

Savbo's right, I think - it is uneven watering.

You must water according to the plant's needs.  That doesn't mean faithfully watering daily, unfortunately.  Sometimes you will need to water x3 daily in pots if it's hot / sunny / windy.  In rainy / cool conditions you will be able to knock it on the head a bit.

If you think about it, the plant will drink up and transpire far more water in the first conditions than in the second, so simply adding the same amount of water daily isn't meeting its needs.  It's about knowing your plants and never letting the compost dry out but not drowning it either.

And no, I've not managed it either this year!