From witchipedia: http://www.witchipedia.com/rosemary#toc4
Rosemary is male in nature and ruled by Leo, the element fire and the Sun (or Moon, depending who you ask)
It's sacred to Hebe, Aphrodite and the Virgin Mary.
Rosemary can be used in spells for fidelity and remembrance as well as to dispel jealousy.
Rosemary is useful for ritual baths, and for making sacred herbal water for ritual cleansing, blessing and purification.
Use rosemary in spells to enhance memory, including those spells for success in school. Also use for spells to retain youth and burn as incense when you are meditating or doing dream work to remember your past lives.
Place rosemary under your pillow to help you to remember your dreams and to keep away nightmares and other unwanted nighttime visitations.
Rosemary may be used in hand fasting ceremonies in a variety of ways.
Burn rosemary and juniper together to aid with healing, and to smudge a sickroom to drive out the negativity associated with disease.
Wear Rosemary oil on those occasions that you want to make a lasting impression.