For the first time, I'll be growing toms in the greenhouse this year. Should I leave the window open when the flowers form, to let insects in to pollinate?
Yes, on warm days!
My mum used to encourage us kids to give the flowering tomato plant stems a little tap whenever we were in the greenhouse, which was supposed to do the same thing ;D
Thanks! I can never remember which plants need pollinators and which will do it alone. :-[
To be honest though, try keeping insects OUT of your greenhouse ...