MemberApril 21, 2008 at 7:24 am
A rule of thumb is 1/3 of the post. This is normally overkill but for a big sign in an exposed location it may be needed. It all depends on the condition of the ground. More often than not a 2′ cubed hole is sufficient but you can never tell till you get digging. Have your posts longer than needed and cut down on site.
And yes, saying hello is polite but not actually required to get an answer to a question.