The meaning of a dream about a Christmas tree will have to do with your feelings about Christmas in real life.
For many people, Christmas is associated with celebrating, so a Christmas tree in a dream can symbolize something that is worthy of celebration, such as an achievement or the beginning of a new stage in life. Christmas is followed by the start of the New Year, so a Christmas tree can represent a new beginning.
A Christmas tree can also symbolize family and togetherness.
Christmas, and Christmas trees, is associated with gift giving, so if you dream about a Christmas tree you may be feeling generous.
If you have negative associations with Christmas, then a dream about a Christmas tree can have negative connotations.
A Christmas tree in a dream can represent an event that occurred at Christmas.