Place the rhubarb, sugar, nutmeg, ginger, zest and juice of 1 lemon in a large mixing bowl and mix it all together. Cover with clingfilm and leave to stand overnight at room temperature.
In a saucepan, simmer the orange peel for 20 minutes. Meanwhile, put a saucer into the freezer to chill. Drain and stir into the rhubarb mixture.
Pour the rhubarb mixture into a preserving pan and stir occasionally over a gentle heat until the sugar has completely dissolved. Then bring to the boil stirring occasionally until the mixture has thickened and setting point is reached.
To test if it’s set. Take a tsp of the mixture and drop it onto a chilled saucer. After 30 seconds, push your finger through the jam, if it wrinkles then the jam will set. If not, boil for another minute or so and test again.
Remove the pan from the heat and pot up in hot sterilised jars.