How many entries? My current thought on this question is one published entry every other day, which gives you the intervening days to locate a passage and consider your thoughts about it. If we start counting from April 1, with that day being a search-and-consider day, this means you have written two entries by today (Tue Apr 5) and are thinking about the third (to be published tomorrow, Wed Apr 6). Remember to review my commonplace book purplemarblemajesty for sample reflections on chosen passages. The reflections written in blue font show recommended depth and length.
Remember the essential differences between a blog’s posts on the one hand, and its pages on the other. Also, remember that organization is a basic function of the commonplace book. It’s one thing to find passages that mean something to you. A extra layer of meaning emerges, once you organize the collection that is accumulating.
In my (evolving, developing) commonplace book, I use pages as the primary organizational tool. You may want to do this, or use posts. If pots is your preferred tool, you can create tags or categories to organize the posts. Somewhere on your blog, you want to indicate how people navigate the organizational structure, the design of the book.