Put rhubarb and ginger in a jar. Pour over sugar, shake and leave in room temperature for two days.
Shake again so the sugar dissolves.
Strain the mixture through a fine mesh sieve or cheesecloth into a clean jar. Press gently to extract as much liquid as possible.
Refrigerate the syrup in a sealed container. It will last for one year.
Use the left-over rhubarb in cake or tart.
