Lager questions

The only "sign of fermentation" that matters in regard to attenuation is the beer's gravity. Is it still changing? 5 weeks is a really long time for attenuation, even at lager fermentation temperatures.

 

After 35 days I would suspect your fermentation is complete, but what I would do is bump the temperature up to 65 or so for 3 days and confirm it's complete with a gravity reading. The temperature increase would accomplish a couple things, it would encourage fermentation to finish if it hasn't and serve as a diacetyl rest.

The first lager I made I fermented in primary for 3 weeks at 50, "confirmed" FG with a couple readings and proceeded to keg. The beer tasted great going into the keg, but after lagering and carbonating at 35 for 2 weeks I tasted a sample and was hit with diacetyl. The FG had not changed, but suspect there were still a lot of diacetyl pre-cursors when I kegged the beer. Ultimately, I krausened that beer and warmed it up to room temperature to clean up the diacetyl and it turned out ok, but far from my best effort.

I brew lagers about 50% of the time now and have adopted a general fermentation profile of ~50 for 5-7 days, free rise to ~55 for 5-7 days, and then bring the temperature up to ~65 for 5-7 days. Following this I keg and lager. Temperature and time depends OG and the yeast I'm using, but this profile has consistently produced very clean, crisp beer. The higher temperatures encourage full attenuation but don't encourage esters since fermentation almost complete.

 

Yeah, you should probably warm this thing up to room temp for a diacetyl rest. Lager "fermentation" shouldn't really take much longer than ale. It's the lagering at near freezing temps that takes time, this is done after fermentation.
My lager schedule usually goes like this: ferment around 50F for 8-10 days, then slowly raise temp up to 65F over a couple days, then leave at room temp for about a week, then keg and lager at 35F for a month or longer.

 

Also, I use 2 packs of yeast, if using dry. But sounds like that is not your issue.

By the way, I like the idea of a lager with maris otter! I've been meaning to try that.

 

Sounds like it is done to me.

 

If you are sure your FG was 1009 there`s no need to worry about bottle bombs cos there is not a bunch of sugars left to be eaten thus not too much Co2 to be added. So you can go either way bottling or leaving it a bit longer at room temp(preferable to me).