Keep the sidebar only for blog pages?

I have been moving my site from http://peterchamberlaincann.wordpress.com to http://www.peterchamberlaincann.co.uk recently.

One thing I want to do is put the sidebar in for all the blog pages, but not for the others. How can I do that? I have a child theme set up that, amongst other things, removes the sidebar.

I believe this is the code I need to put in to get the sidebar back:

.entry-meta {
    display: inline;
}

.wide {
    float: right;
    width: 520px;
}

.hentry {
    margin: 0 0 40px;
}