Probably a bit of a how long is a piece of string question, but worth a try.....
It's our first year with the polytunnel. 60ft. West Wales. The temperature this weekend is scheduled to get down to 1 or two degrees outside. I have tender plants, tomatoes, courgettes and so on in the polytunnel (still in pots) and they are doing well.
Any opinion on how much warmer it will be in the polytunnel? does it tend to give say 3 degrees of protection, or 5 degrees? Rough guesses will do. At the moment, I think I'll bring all the tender plants into the house, until the colder period is over, but I'd appreciate opinions.
Thanks in advance.