Windowsills as a substitute for a greenhouse
Ignorant newbie question alert!
Gardening experts sometimes write that if one doesn't have a greenhouse, a windowsill is a suitable substitute for starting e.g. cut and come again salad leaves etc.
Well, I don't have a greenhouse - not yet, anyway - but I do have quite a few windowsills. I'd love some advice on which aspect is best (is south-facing too hot? is north-facing too dark?) and also any insights on how to make this work.