Q.Tomatoes splitting open
I have one tomato plant in a large container and the tomatoes are splitting open before they ripen. I have read that it is too much rain/water. Can I do anything to fix the problem or is it too late?
It's not exactly too much water, it's that the plant didn't have quite ENOUGH water before it got a lot (of water).
There's unfortunately nothing you can do about the ones that are already split but this article will give you some tips on how to prevent your tomatoes from cracking in the future:
https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-cracking.htm