Rosemary is one of the flowers that traditionally make up a Marian garden. According to one source, the others include:
CHRISTMAS ROSE, SNOWDROP, LILY OF THE VALLEY, ROSES , LILIES, FLEUR-DE-LIS, JUNIPER, GERMANDER SPEEDWELL, VIOLET, ROSE OF JERICHO, ENGLISH MARIGOLD, CUCKOO FLOWER, CARNATION, and SEA-PINK.
I have referenced these in past posts; some of which are highlighted in red above. A more extensive Marian Garden explanation is offered here.
You often find Rosemary sold as a plant and in decorative holiday sprays this time of year but, often the symbolic reason why it is festively featured (not only because it is tasty) has been lost in today's popular culture.
The Flight Into Eygpt
According to legend "The rosemary bush gave shelter to the Holy Family during the flight into Egypt. It is told that Mary hung the linens of the Holy Child on the rosemary bush to dry, and afterwards it became aromatic and evergreen, with little blue flowers springing up from its branches." more