Ginger essential oil, Zingiber officinale, has a warm, strong, spicy aroma. Ginger can be calming yet also act as a stimulant. Within muscle and massage formulations, it helps to relieve soreness and stiffness in muscles and increases circulation. It also can strengthen the immune system during the cold season. Ginger oil blends well with citrus oils, sandalwood, frankincense, cedarwood, and palmarosa. Ginger oil is very strong, and it must be diluted significantly before using on skin or in the bath. Use it with caution during pregnancy.