Boil the water and let it cool to room temperature. Or use bottled water, then you don't need to boil it.
You don't need to peel the ginger. Just wash and cut into smaller pieces. Blend the ginger with a suitable amount of water or sea buckthorn juice in a blender.
Combine all the ingredients and let sit for a while. I would say a minimum of 30 minutes.
Strain the juice with a cheesecloth or similar, put in bottles and refrigerate.