Watering regime at 3 months old

I'll probably have to go away in December for a couple weeks. My plants wil be about 3 months old by then. If I were to get a friend to tend to them for the time I'm gone, how often would they have to come water them? Would there be a difference if I was in vegetative or flowering phase? Do the plants take less water in one of those phases?

I have ventilation and the light on a timer, etc... so what is the easiest way to keep them well while inconveniencing a friend as little as possible?

Thanks!

by 3 months they should start flowerin, and they will not need nemore water than what you usually do, so like every 3-5 days you can water id say.