The Christmas tree should be put up as soon as possible after Thanksgiving, so you can fully enjoy the Christmas season. It's a great way to get in the holiday spirit and make your home feel more festive. It's also a good idea to keep the tree up until January 6th, which is known as the Epiphany or Three Kings' Day. This is the day when the wise men are said to have brought their gifts to the baby Jesus, and it's a wonderful way to celebrate the end of the Christmas season.