You can always allow automatically comments on the blog by logging into the Admin area ->Control Center->Blog setting and change it to put:
Enable comments for all posts by default. Comments can still be enabled/disabled for certain posts when creating new posts or editing old ones.
Notification of new comments.
Or you can do that on each article you put on your blog by editing the article and looking at the right hand side column where you can allow column and get notifications so you know when new colums have been posted.
I remind you also that in order to prevent spams, you can read:
If you receive spams, you can always untick Enable comments in your articles at a later stage, and spammers won't be able to post new comments anymore. This is a very strong method, and instead you may prefer to Moderate the comments, so displaying only comments that you validate before.