Grate the ginger, quantity depending on how spicy you'd like the beverage. 0.5 oz (15 g) of ginger for 1 gal (4 L) water are more than enough.
Pour the bee pollen in a large jar with a nozzle for better presentation. Squeeze out the juice of 4 lemons into it, cut the 5th with the rind, washed beforehand, and add it too. Pour in the honey and top off with water.
I used spring water since I don't like soda but I think you'll probably like it even more with carbonated water. Add the nutmeg and ginger.
Stir everything until the honey dissolves. Leave it to sit for 1-2 hours. Serve in beautiful glasses decorated with lemon slices and sprinkled with salt.