hydrosol is the water that's left over from the distillation process that creates essential oils. They have microparticles of the original plant material and are scented, flavorful and have many therapeutic properties.
Verbena herb is known for it's effects in dispelling depression and countering nervous exhaustion and anxiety. Great for headaches and migraines and is said to be one of the best palliatives for the onset of colds and flu. It is reputed to be a good daily mouthwash as it's strong anti-inflammatory ability has a strong affinity for the mucus membranes of the mouth and nose.
Internally it will settle a nervous stomach and indigestion, as well as being very pleasant to drink. A tablespoon of hydrosol in a liter of seltzer is wonderfully refreshing. It could also be added to a pot of tea. It's flavor is distinctly lemon but not citrusy, and much less potent. Imagine it in desserts, or with seafood.
Verbena Water by Herbal Alchemy can be bought here.