Maralroot Culture and Roseroot Culture

My question is about two plants: maralroot and roseroot. I bought both as plants about three years ago. Both are doing poorly. They both come up for a short time and then die back for the season.
The maralroot is in full sun on the corner of a bed. I must confess to having kept it in a gallon pot, sunk in the ground, because I wasn't sure what to do with it.
The roseroot is in a 2 gallon pot, also sunk in the ground under a fir tree that gets plenty of sunlight but also some shade.
I love Richters Herbs but the lack of information about how to grow these and other plants can sometimes be frustrating. Do they need sun/shade? Soil conditions? Any help will be greatly appreciated.

Actually the 2006 catalogue says that maralroot likes deep, well-drained, fertile soil and full sun. A pot may be too restrictive for a plant that likes deep soil.
Roseroot is less fussy and just likes a well-drained spot in full sun. If you keep it too hot and dry it becomes dormant. We found that out in the summer of 2005 when it was so hot that we could not keep the plants cool and moist!