There is no private setting for the blog but you can turn off comments. But yes, you can cut & paste, use BB codes, and no one else could ever update it, only you have complete control of it. There is a save and preview feature that allows you to edit, correct format, add photos, etc. and when you are happy with it, publish it. Further editing can be done at any time.
Some use it for tracking seed growing and I've seen many that simply use it as a journal, nothing interesting for others to read.
Here's an older post of mine I wrote in my favorite color, green:
https://garden.org/blogs/entry...
