Not quite sure what you mean, Jremington!
He is talking about if you want all three valves to come on together, then you just power them in parallel off the same relay. But that doesn't sound like what you want. It sounds like you want the valves to be individually controllable, in which case you're going to need three pins.
What is the point of this exercise? Are you out of pins or something? That is a much easier problem to solve.