Aromatically, Spearmint Hydrosol is one of my favorites. it is much lighter in aroma than is the essential oil. Spearmint Hydrosol smells more like an infusion made from fresh spearmint leaves than it does Spearmint Essential Oil.
Up to 2 years if stored properly (refrigeration is recommended).
Reported Properties, Uses and Applications
There isn't much formal documentation about Spearmint Hydrosol, but I personally find it to be extraordinarily refreshing, uplifting and energizing without being as intense as Peppermint Hydrosol or the mint essential oils. I keep a bottle in my fridge and enjoy misting it on my face when hot or exhausted. I love it as a foot mist for tired feet as well. Len and Shirley Price mention that Spearmint Hydrosol possesses the following properties: "analgesic, anti-inflammatory, digestive." [Len Price and Shirley Price, Understanding Hydrolats: The Specific Hydrosols for Aromatherapy: A Guide for Health Professionals (London: Churchill Livingstone, 2004), 127.]
Read AromaWeb's Hydrosol Safety Guidelines.