Put it this way, toms will grow outdoors with daytime temps of roughly 17C+ in full sun for at least 6-8 hours a day. They will still survive happily outdoors at lower daytime temps but will take a lot longer. The ideal is mid-20sC and higher. Again, in full sun for at least 6-8 hours a day. Overnight temps for outdoor toms need to be at least 15C to develop properly. Toms actually do a lot of their growing overnight. Again, they will cope with less, but take a lot longer.
I don't know when you're going away but, till you do, leave them out all day (protected if there's rain.) Barring any sudden massive drops in temperature, every couple of days add a couple of hours to their stay outside. It's called "hardening off", getting them gradually acclimatised to the new conditions.
Potatoes? Some English friends brought me over two first early varieties and a second early variety. We've had rain and warmth and the plants are climbing out of the ground.