What do you mean by "using"? Using in the boil or using in place of dry hops after fermentation?
I just tasted my first fresh hop beer of the season last night after transferring to secondary and it blew me away. the fresh hop nose and flavor was already there. This morning I put in 2 ounces of frozen fresh hops (frozen at the time of the boil) in each 6 gallon carboy. They smelled pungent and wonderful going in. I don't think they will impart a grassy flavor but I will come back and let you know. I used a pretty robust malt profile for this 12 gallon batch of fresh hop red and about 4 lbs. of fresh hops in the boil at various stages. The hops in the boil (and the dry hop) were Newport and Cascade, with about six ounces of Chinook, Brewer's Gold and Willamette that went into the mash.
I have a lighter bodied fresh hop IPA with Nugget and Cascade that is a few days behind the red and I plan to do the same as far as dry hops. And for my craziest friends (and me) I am going to stick two ounces of frozen hops in an oversized tea ball and put it directly into one of the corny kegs.
I know, I know - some of you are screaming "Contamination!" - but I don't think so. I think the worst that will happen is that I might drink a ladybug or an ant.
Wow. I had a Founders Harvest Ale last year and it was fantastic! IMO. I really couldn't believe how fresh and tasty those hops were! I'm really looking forward to this years''harvest, and trying to bulk up my savings account to pay for all that fresh hop goodness!
Unfortunately, I didn't plan ahead when I dried out my own homegrown hops, so I'm screwed for doing my own homebrew version.