All throughout the day....
The only guaranteed bowlpacks are right after I wake up and right when I get home from work. After that, my tree's fair game whenever I want. Typically.... on average.... I guess I'd say I'm packing a bowl every hour, hour and a half. Bowlpiece isn't big at all, though, only 3 hits from green to cashed and that's if I make an effort to get 3 hits out of it.
I go through about a gram a day pretty consistently, though. Weekend consumption probably jumps up a little bit, but I'm pretty good at making 7g last seven days (or 14g for 14, 28g for 28, etc etc), regardless of how much I actually smoke per day.