@Aussie_Kiss: Respectfully, and I say this as an avid and fairly advanced home-brewer myself, I think adding yeast and sugar to PST wash and trying to ferment it is an awful idea. It violates all of the german purity laws, for one thing

But more importantly, I think it's going to taste horrible, if the yeasties even have enough nutrients to ferment it down. My guess is they will start on the sugar but, unable to reproduce without the trace minerals and other nutrients found in wort, they won't last long enough to fully attenuate. And if they do, well, fermented sugar water is pretty nasty. If you're going to try this, I'd at least try it with malt extract, and make a standard batch except do a PST infusion instead of adding carapils or other flavored malts as the water is coming up to temp.
It's an interesting idea for sure. I have half a mind to try it myself -- kind of a modern-day laudanum -- but if I ever try it, I'll do as above and make a batch of real beer, and also I'll use fresh pods from the garden vs a bag of seeds.