I don't know of any Christian so completely oblivious that they're unaware of the liturgical calendar - specifically the celebrations of Christmas and Easter. Many also understand and appreciate the significance of Advent (the weeks building up to Christmas) and Lent (the period between Ash Wednesday and Easter) or at least Palm Sunday as the start of Holy Week.
But how many of us really appreciate all of the depth and significance that accompanies the full liturgical calendar? For example, we're currently in the Season of Easter. This is the period between Christ's resurrection (Easter) and Ascension, ending with the celebration of Pentecost (the coming of the Holy Spirit).
Easter is the season when we, as Christians, come into ourselves. This is a time when Christ's followers came to appreciate Christ as the Messiah, having risen from the grave and fulfilled the words of the Old Testament. Christ appeared to his disciples several times, ultimately telling them to go and spread the message.
The Easter lilies in my garden remind me that Easter is not about the day, which abounds with hothouse flowers forced to bloom on schedule. Rather, it is a season of hope and anticipation of the things to come.