Blogger is on a roll!
Just want to let you know that Blogger has activated their Search Description not only for the Blog itself (i.e. Blog Description), but for every post! This means you can edit the meta description on your every post. See the red arrow below to locate the meta description of a link on a search engine result page.
So as you are writing your new post on Blogger, pay attention to the right column where you would find the Search Description box. Remember, ideally this Search Description should contain about 155 characters.
Read more about what Search Description really is, check out Blogger Support Page.