HI and Merry Christmas to all!!

I got a small Blueberry plant from a garden center that was closing in
Sept. Its in a 6" pot and it was about a foot tall with a few berries
on it when I got it. I live on the line between 5-6 St Louis area
and I know I need to acidify (is that the right word??) the soil so I
got some aluminum sulfate but I never did anything with this guy.
Should I plant it now or WHEN???
The temp around here now is about 25 F. Educate Me thanks Joe Mc