Advent Candles and wreath

The wreath's symbolism of the advent (coming) of Light into the world is clear. The gradual lighting of the four candles, one on each Sunday of the Advent season, combined with the liturgical colors of the candles (purple is the penitential color used during Advent and Lent; rose is a liturgical color used only on Gaudete Sunday in Advent and Laetare Sunday in Lent) help to symbolize not only our expectation and hope in Our Savior's first coming into the world, but also in his Second Coming as Judge at the end of the world.

The wreath itself is also symbolic. The circle of evergreen in which the candles are placed represents everlasting life. The seedpods, nuts and cones used to decorate the wreath are symbolic of resurrection, and fruits represent the nourishing fruitfulness of the Christian life.

Source : Catholic. org