Christians of both East and West have, from very early times, blessed herbs and fruit on the Feast of the Assumption. Thus blessed, these creatures become sacramentals of the Church and portents of divine protection from dangers to soul and body. In some places the herbs were placed on the altar, and even beneath the altar linens, so that from this proximity to the Most Holy Eucharist they might receive a special hallowing, beyond that conferred by the blessing prayers of the Church.
The prayers of the rite suggest that this custom of the Church hearkens back to the ancient customs ordained by God through Moses. According to Christian tradition, when the Apostles accompanied Saint Thomas, who had been absent at the time of the Blessed Virgin’s death, to her tomb, upon opening it they discovered that her body was not there. Instead, they found the tomb filled with fragrant herbs and flowers. Blessed herbs recall the lingering fragrance of the virtues of the Blessed Virgin Mary in the Church.
Blessing of Herbs and Flowers in Honour of the Assumption of the Blessed Virgin Mary