Harvest wreaths, a common household decoration today, are a custom with ancient roots in Europe. The creation of harvest wreaths in Europe can be traced back to ancient times, and is associated with animistic spiritual beliefs. In Ancient Greece, the harvest wreath was a sacred amulet, using wheat or other harvested plants, woven together with red and white wool thread. The harvest wreath would be hung by the door year-round.
Harvest wreaths were an important symbol to the community in Ancient Greece, not merely to the farmer and his family. The festivals devoted to Dionysus, the Oschophoria and Anthesteria, included a ritual procession called the eiresîonê. A harvest wreath was carried to Pyanopsia and Thargelia by young boys, who would sing during the journey. The laurel or olive wreath would be hung at the door, and then offerings were made to Helios and the Hours. It was hoped that this ritual would bring protection against crop failure and plagues.
In Poland, the harvest wreath (wieniec) is a central symbol of the Harvest Festival, Dozynki. Wreaths are made of different shapes and sizes, using harvested grain plants, fruit and nuts. The wreath is then brought to a church for a blessing by a priest. The tradition includes a procession to the family home from the church, with a girl or young woman leading the procession and carrying the wreath. The procession is followed with a celebration and feast. Ukraine, Hungary, and other Eastern Europe cultures also have similar rituals that began as part of pre-Christian culture.
(the slideshow: a part of my wheat wreath collection)