Greenhouse temperatures

[stevemac]

Hi

This is my first year with a greenhouse .
During the day i have various tomatoes/peppers/chillis/cucs/basil and more in it.
I bring all of these in at night .
However my question is,at what temperature is it Ok to leave these plants in an unheated greenhouse overnight without damaging them?

[rana]

Different plants require different temperatures. In your list I would say a minimum of 45 degrees fahrenheit (I think thats about 7C) if the plants are beyond the small seedling stage - say a month old.

Remember that the air in the greenhouse is fairly still so there is no wind chill so the plants can put up with occasional low temperatures. If it is too cold the tomatoes will let you know by turnng blue.

[Capsid]

I have had all of those plants (except basil which stays indoors on a windowsill) in an unheated greenhouse for several weeks now and do not bring them indoors at night. Their growth slows down a bit but they will not get damaged now, the greenhouse will keep off the frosts which are not as cold or long lasting at this time of year.

[stevemac]

Thanks for the replies.

I have one of those max/min thermometers and the nights seem to go down to around 4-9C.
Obviously i dont want to kill any of them at this stage so i am away to find out about Blue tomatoes!!!

[kentvegplot]

My greenhouse is getting down to about 5 on the colder nights and everything seems fine. I do keep a piece of fleece handy and would cover some of the smaller plants if frost threatened (and I haven't needed it for some days now).

[Lorraine70]

I'm in Northumberland and have tomatoes, cucumbers, chillies, salads, herbs etc growing onin my unheated polytunnel. I do fleece the cucumbers on particularly chilly nights as otherwise they tend to get very droopy when the polytunnel temperature increases during the day. The tomatoes have been in their growbags for a couple of weeks now and I've had no problems even when the temperatures outside have dipped to just above freezing.