Your hubs are already optimized for google+ allowing others to +1 them. If you build up your own google+ community (of friends and family, and others who share your interests) you can share your hub there just as you would on facebook or twitter.
When I publish a hub I share it on facebook, twitter, and google+. Maybe one of my followers in each of those places will be interested in it. I do post other content and other hubs to those places just so I'm not spamming my own articles.