Problem with my Chilli Seedlings

I've never tried chillis or peppers before, so I thought I'd give it a go this year. The chillis are coming up nicely, but this morning a couple of the seedlings were drooping over. They are just starting to develop secondary leaves, so I wondered if the problem might have been that the thin stems couldn't handle the extra weight - this kind of makes sense because the leaves close up at night, making the seedlings taller / heavier in the morning.

For now I've shored them up with extra compost, but does anyone have any ideas what else might be causing this?

 

I forgot to add - they are kept in a greenhouse in direct sunlight, and the temperature got as high as 110f yesterday. I know they aren't drying out, and the basil and everything else in there is coping fine - I would have thought the basil would be the first to show signs if it was temperature related, but I've really got no experience with greenhouse growing

 

I have been growing chillis for about three years now ,I'm not an expert by any means but I have had a similar problem in the past I thought maybe the soil just got to hot damaging the root which might make the plant droop over. Hope this is of some help.

C

 

That's definitely helpful, thanks dalbuie. The roots weren't that well developed when I moved them to larger pots, so that might well be the cause - I'll have to look for somewhere cooler.

 

Will, when I went in my greenhouse this morning my capsicum plants were also limp and bent over, they perked up later though.
I wounder if its to do with very high daytime temps. followed by fairly low night temps.