If someone – and let’s just for the sake of argument call that someone “me” – used “Magic Switchin’ Secret” Kool-Aid to dye some wool this past summer, and it turned out that they didn’t dye quite enough for the project, and then all grocery stores within the closest three cities stopped selling that flavor of Kool-Aid, (whatever flavor it is, I can’t imagine actually drinking the stuff) either because it is winter or because they hate me, I’m not sure, then in desperation the colour can be matched pretty well with food coloring in the following proportions:

5 drops green
5 drops yellow
1 drop red

And don’t forget your vinegar.  More information on food dye colouring in this Knitty Article.