The Easter season ends on Pentecost Sunday. The liturgical color of that day is red in honor of the Holy Spirit. Occasionally the liturgical colors change within a season (e.g., rose on Gaudete Sunday in Advent and Laudare Sunday in Lent), but that does not necessarily mean the season itself has changed.
__________________ "If anyone comes to me, I want to lead them to Him." --St. Edith Stein