I have used a hops/barley mixture quite often on my garden (from a local micro
brew pub, and my own "nanobrew" system). It seems to be a fine soil additive.
I don't even compost it--just dilute it a little and broadcast it on the soil
between plants.

I will warn you about a crazy problem that i had THIS particular spring. I
also have a freind who runs a coffee shop, who saved about 10 gallons of coffee
grounds for me. So one afternoon, I spread about 10 gallons of coffee grounds
and about 20 of brewery waste on my soil in the spring.

The next morning (a saturday) I went out to till all the stuff in, but
suffering from a severe hangover, was unable to do it. Once the sun hit it and
it warmed up, it just reaked of stale beer and coffee!!!

The smell goes away quickly, within about a day after a good watering.