Put the grapes in a medium sized mixing bowl. Sprinkle some chopped parsley on the grapes and then pour in 250ml of freshly squeezed lemon juice. Mix them all together with a wooden spoon. Also add lemon zest and 2 teaspoons of honey for flavour.
For the dressing: pour in 500ml of grape juice into another bowl. Put 3 tablespoons of honey and 5 tablespoons of mayonnaise along with the remaining lemon juice. Add a little if the dressing is too thick. Mix together.
Pour the grape dressing over the salad, toss and serve cold.