Lavender:

Promotes relaxation: The University of Maryland Medical Centre reports that scientific studies suggest that inhaling the scent of lavender may slow nervous system activity, promoting relaxation. This can help with anxiety, insomnia, stress and depression. Preparing lavender tea helps release the oils responsible for the beneficial aroma. Digestive Issues: Modern studies suggest that the smooth muscle in the intestines responsible for moving food through the digestive system would relax when lavender oil was applied and reported that lavender oils protected against the formation of gastric ulcers and relieved indigestion. Lavender oil has been found to be a benefit in reducing both muscle spasms and convulsions.

From "Journal of Ethnopharmacology" and “Life Sciences” journal.