Did Hildegard of Bingen write both the poetry and the music for Alleluia O virga mediatrix?

Yes, Hildegard of Bingen composed both the poetry and the music for "Alleluia O virga mediatrix." This piece is part of her larger body of work, which includes numerous liturgical songs and texts. Hildegard's compositions are known for their unique melodic lines and spiritual depth, reflecting her visionary experiences and theological insights. Her contributions significantly influenced medieval music and mysticism.