Mixing yeast
 

hi I have a wyeast german ale that was out of the fridge for a couple of weeks so I guess its toast. So I bought a wyeast american II but it says on the website that is fruitier than the american ale so if I mix the german ale that has been out of he fridge with the american II, will it have a positive outcome? maybe a balance between sweet and dry?

generally one yeast tends to take over and dominate the flavor profile. I'd guess it'd be the american II in this case since it's healthier yeast.

Make a starter with the German yeast and just use it.

This can happen but it's much more of a problem if you're harvesting yeast to reuse over multiple generations. Mixing two packs should give you a blend of flavors, otherwise the major manufacturers wouldn't bother selling yeast blends.

I think in this case using two packs of yeast would be better if you're not going to make a starter. Pitching rate is the most important thing. If you want the profile of just one yeast, make the appropriate sized starter.

but can it spoil the batch if I mix them? Also, for 5 gallons of wort, one wyeast pack is enough right?

It definitely will not spoil the batch to mix them, and no, a single pack is not good for a beer with an OG much over 1.030, despite what it says on the package. There is enough yeast to ferment the beer, but not enough to ferment it optimally by a long shot. You may get off flavors or poor attenuation by underpitching. Try using the calculator at mrmalty.com to see how badly you've been underpitching and I'm willing to bet you'll be much happier with your beer after pitching the correct number of healthy yeast cells.

so, 2 wyeast packs is enough?

You have to calculate the number of cells you'll need based on the age of your yeast and the gravity of your beer. Use the calculator. It knows.

For now, use both packs as 1 definitely isn't enough. 2 might not be enough, we don't know anything about your yeast or beer.