It kept them away for a few days. After the rain, it didn't have much affect as a barrier, because it dissolved into the soil and the scent disappeared.
The only way I know how to keep the squirrels out all season is with fencing/screens, or almost daily application of odors to the soil and plants. It isn't very conventional. I think I'm going to try laying a screen over my soil for a while, like I do to protect my apple trees.