Ailing tomatoes

[ClareJ]

Hi there, this is my first year of growing and I currently have a number of moneymaker tomatoes growing in my friend's greenhouse. They were all doing fine until about two weeks ago when some of the ends of 'branches' and leaves started going mouldy - horrid long stuff. The greenhouse doesn't have a vent, so gets quite hot and I wonder if I watered them too much and it got too humid in there? I've reduced the watering (only if they go below 80% on my two pronged measuring thing) and have left the door open much more, and they seem much better.

Does anyone have any ideas;do you think I'm right?

Thanks

[rustylady]

Definitely right to increase ventilation. Do you have any pictures of the horrid long stuff?

[taff]

it might have been botrytis. It likes humid conditions, so yes, you've done right

[zazen999]

Why only water when below 80% on your two pronged thing?

[ClareJ]

Why only water when below 80% on your two pronged thing?

Well, 100 says wet and 50% is moist, so as I assume that I have been overwatering I've been letting them dry out some...

[ClareJ]

Definitely right to increase ventilation. Do you have any pictures of the horrid long stuff?

I've removed most of it and it's return seems to have slowed; there was one mouldy leaf and a branch stump today...

[Potstubsdustbins]

Looks a lot like Grey Mould (Botrytis) to me.

Colin