Thanks alround for the advice – much appreciated.
I’m very new to growing my own food and it’s something I’m greatly enjoying. However, sometimes I try and run before I can walk. I think this coming spring I shall have a go at propagating somewhere warm inside and then consider one of the kindly recommended electric propagators for next year.
Maybe Father Christmas will bring me something anyway? 
If so, is it advisable to move freshly germinated seedlings to a cooler area inside the house before moving them outside into the unheated greenhouse? Just wondering if it would be too much of a shock going from warm propagator to underglass outside?! Hardening off process etc.
Thanks again,
Tris