This was one project that I didn't do myself. The boards were attached
to the fence posts. If you have to retain more than about a foot of
dirt, you'll want to provide additional support for the retaining
boards, I'd think. The boards are exposed about 1-2 inches. If you
face the boards with a couple of layers of heavy plastic, the moisture
load on them will be less until the plastic rots away, which it will do
in a few years. I did that on a short retaining wall, but I didn't use
PT on THAT project and the boards eventually had to be replaced due to
termite damage encouraged by the moisture in the wood. PT should last
over 10 years, easily.

The boards the fence co. installed were just butted together. The
boards haven't shrink much in length, so I wouldn't worry to much about
that aspect of the installation.

Dave

Meatball wrote:

Thanks David,
Just the answer I was looking for and from someone who has done this!
I plan on using PT wood...
Couple of other questions:
How deep did you dig ie is each 2x12 buried to the surface?
I'm thinking burying and leaving a couple of inches exposed
Anything else done to the wood...or just use back fill and fence to
hold in place?
Since I have a grading going from 6 to 24, should I use 2x12 by 8 feet
long?
Did you connect boards?
Thanks for your quick response.