Next time find some green nuts. They allow an uncut wire to ground for at least one device (the box if you have metal boxes.) With your plastic boxes you'd use the uncut ground to one device and another ground from the nut to the other one.
Or do it like I do (eh, I am the village idiot!) and use one ground, loop around the first device's ground screw, and then to the next device. No wire nuts, and no way to accidentally un-ground a device.
