I have to control myself and not start decorating too early. By August 1st I'm already thinking fall and Halloween, but I try to control myself until at least September 1st before I decorate for fall. I dont always suceed though!
November 1st I take down Halloween and put up Thanksgiving, but my poor turkeys never make it to Turkey Day because I just can't wait to put up my Christmas items.
I do tend to take my decorations down fairly quickly. I think because I put them up so early it feels like it's been long enough for me.