No Christmas Decorations During Advent?

The Church counsels that we should wait until Christmas to put up decorations. That is, in anticipation and preparation of the Christmas Vigil after Mass on the last day of Advent.

The Church provides binding liturgical guidelines in the General Instruction of the Roman Missal (GIRM). Regarding the decoration of churches, GIRM 305 provides:

Moderation should be observed in the decoration of the altar.

During Advent the floral decoration of the altar should be marked by a moderation suited to the character of this season, without expressing prematurely the full joy of the Nativity of the Lord. During Lent it is forbidden for the altar to be decorated with flowers. Laetare Sunday (Fourth Sunday of Lent), solemnities, and feasts are exceptions.

Floral decorations should always be done with moderation and placed around the altar rather than on its mensa.

In addition, in 2000, the U.S. Bishops issued general liturgical guidelines in Built of Living Stones, which in its preface says:

The document presents guidelines that can serve as the basis for diocesan bishops to issue further guidelines and directives for their dioceses. Where the document quotes or reiterates norms from liturgical books and the Code of Canon Law, those prescriptions are binding on local communities and dioceses.

In addition, in chapter two (“The Church Building and the Sacred Rites Celebrated There”) of Built of Living Stones, the U.S. Bishops counsel:

These seasonal decorations are maintained throughout the entire liturgical season. Since the Christmas season begins with the Vigil Mass on Christmas Eve and ends with the baptism of the Lord, the placement and removal of Christmas decorations should coincide with these times. Since the Easter season lasts fifty days, planning will encompass ways to sustain the decor until the fiftieth day of Pentecost.