I wanted to pop into this thread as I'm actually planning to do a similar job and wanted to get some feedback about the post installs as well.
I plan to build my own cedar fence panels and I also wanted to use cedar 4x4's for the posts. I have been doing some reading at various places on the web and some people have commented that cedar 4x4's have only lasted 5 years. Obviously, the work to build a fence I really don't want to be re-doing this in 5 years time so I was hoping to get some "to the point" details about installing the cedar posts properly so that they will last as long as possible.
I found a post plan on the web and it was not specific to cedar but the way it was done was as such:
Base of the hole and bottom 24" of the hole was filled with pea gravel
Roughly 8 to 10" of concrete was used for a plug
Top of the hole was back filled with dirt, top 2-4"
I live in Canada and we have nasty cold winters to blistering hot summers so whatever advice I can get for the post installs would be really appreciated. I plan to buy 10' 4x4's so I will be getting at least 3' of post into the ground.
You guys have talked about treating the portion of the post in the ground. Are you just using any stain or is there a special treating that can be used. Should I use concrete or not at all? I had kind of figured the concrete plug idea was one of the better ways to go but maybe not?