Christmas wreaths are traditionally made of evergreen branches or sprigs, which are green year-round and symbolize eternal life. They can also be made with other materials like holly, ivy, pine cones, and berries. Some modern wreaths are made of artificial materials like plastic or metal for durability. The circular shape of the wreath represents the circle of life and the never-ending cycle of the seasons. It is a beautiful and timeless symbol of the holiday spirit.