bill - 1:44 am on May 30, 2013 (gmt 0)
HootSuite is the only big management system that can post to G+, but it can only post to Pages, and even then there are tons of errors. I've tried to use HootSuite to schedule posts to a Google+ page, and most of the time the content never gets published. There will be an error, but you're never notified of the error.
With Google+ it's probably better to post manually as they don't have a public API.