You'll just have to keep checking back. You'll know when you have to water the plants when the soil starts to dry, which will be very visible. If you let it get too dry, the amount of berries they'll reap will be reduced. The times you'll have to water them will vary with the berry's growth time.
Did your parents lock you out of wifi on purpose? Or was it by accident? Oh yeah, that does stink. I'm not much of a battler though. You'd probably destroy me pretty easy xD I know what you mean. I want to get AR for the same reason. I'm not sure if I'll be able to though. And heck yeah! It's totally fun being a game nerd