I believe there are three things that are important when trying to increase feedback on your blog:

Firstly it depends on the size of your audience. If no-one is reading your post then no-one will reply. Therefore you need to increase visitors by building an rss feed following, twitter following & building links to your articles.

Secondly it depends on the content of the post, is it commentable? Is there anything to question, discuss or add to what you have said or have you asked any questions? For example this post is quite personal, I doubt many people will have much to say. But other posts here have been debatable and have had much more feedback.

Finally it depends on your level engagement with your readership. Is it a conversation or a one way communication? You should comment on other people’s blogs, and link back to them where the content is similar or relevant. Engage with people via different social media & you will find they engage back – this is not a quick and easy process – you have to be genuine and build real relationships with people.