Hydrosols, also known as floral waters, are aromatic waters produced through the steam distillation of plant material, such as flowers, herbs, or other botanicals. They are the by product of the essential oil production process.

During steam distillation, steam passes through the plant material, extracting both the volatile essential oils and water-soluble compounds from the plant. As the steam cools and condenses, it separates into two layers: the essential oil, which floats on top, and the aromatic water or hydrosol, which collects beneath it.