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I've got two tomato plants growing outside - first time I've grown them. Some of them have little brown patches appearing on the bottom which then seem to spread and go rotten. The ones that are affected turn red really fast whereas all the others are still really green.
I've been pulling off the manky ones but would like to know what it is and what I can do about it.
Any ideas please???   ???

blossom end rot - caused by unequal watering. It will not spread - nothing you can do!
See thread BEM for more.

WSL - thanks for that. Tim's toms look exactly the same as mine  :(
There have been a couple of times I thought the OH had watered them and he thought I had watered them and of course, neither of us had! So we have only ourselves to blame!

Live and learn eh?  :)