October 1 is my goal to begin, though usually the first weekend in the month is the actual date. The biggest determinant, though, is the "nag quotient:" How much of my wife's pestering can I stand before I give in and do as I'm told. ;>
I'll already have fall stuff up in late September anyway, so there comes a transition time between "fall" and "Halloween." Right now it looks a little odd with creepy tombstones, my reaper, and skeletons, and happy, smiling scarecrows. I'm really hoping to build a Pumpkinrot-style scarecrow to chase away those insipid hay-stuffed ones.
There is a bit of a battle between me and my wife, because I like the darker look of Halloween and she is all too willing to have tschotskes and sillier holiday fare. Basically it's become a split where she decorates the inside of the house with her quirky stuff and I can delve into the black arts outside. However, we do like to have it up no later than two weeks before Halloween so that we can actually enjoy the look of the place along with all of our neighbors.
Rich