Just a quick reply to your bog query.  I live about 40 minutes from 
Niagara Falls, in Ontario Canada.  I've had some form of outdoor bogs for 
about 10 years or so.  We live in USDA climate zone 6 with winter 
minimums of about -25C (you can check a USDA zone map for accurate winter 
mins).  Anyways.  I've grown S. purpurea purpurea, S. purpurea venosa, S. 
flava, S. rubra rubra, S. minor outdoors for years.  The most successful 
has been flava. Infact I've found natural hybrids between my northern 
purps and Georgia flavas in my bogs.  I've made my bogs out of 30 cm deep 
kiddie pools.  I fill it two thirds to the rim with peat.  I then remove peat 
from the centre, and hill it up around the perimeter of the pool to form a 
depression in the centre.  This I fill with live sphagnum.  In that 
depression  I grow plants can expect to find in sphagnum bogs, my native 
purpurea, drosera, native orchids, cranberries etc.  Because this area is 
drepressed, you can keep a very high water level, just like in the bog 
habitat.  Around the perimeter, I mix in in quartz silica sand to make a 
1:1 mix of peat sand that goes down about 10cm or so into the peat.  In 
these, drier, higher areas I plant my flavas, rubras and so on.  I've 
never worried about covering it up, I'm sure if you did, you could 
probably grow all Sarrs outside.
How mild are your winters?
I know a gent in washington DC who grows all his Sarrs outdoors year 
round. Leuco, wherryies, gulfensis, oreophila, the works! He grows them 
in beds formed from railway tie type wood.  He fills them with local 
coastal plain soil! I also know a gent on this list, in NJ, who grows his 
Sarrs outdoors as well.
Good Luck
Carl