A basic summary of the church year and liturgical colors:

Advent  (Blue)
Christmas (White or Gold)
Epiphany (Green)
The Baptism of the Lord (Green)
Transfiguration Sunday (White or Gold)
Ash Wednesday (Purple)
Lent (Purple)
Holy Week (Purple)
Palm Sunday (Purple)
Easter (White or Gold)
Pentecost (Red)
Trinity Sunday (White or Gold)
Days after Pentecost (Green)
All Saints Day (Red)
Christ the King Sunday (White or Gold)