When to decorate for Christmas??

When to decorate for Christmas?? I am the type of person that puts my tree up days before Christmas. I start making Christmas ornaments and preparing for the holiday around December 1st but I do not put any decorations up until around the 12-15th and no tree up until the 20th at the earliest. Wyatt's birthday is in the beginning of December so it is great to not focus on the holidays too much before his birthday so he still gets his own special time. Growing up we always decorated our tree on Christmas eve and we loved it! This year I think we will start decorations on the 14th and the tree is going up on the 21st.

When do you start decorating for the holidays and put your tree up? Is there a reason you do it when you do?