Least Amount of Blog Posts
The absolute least amount of blog posts you should make is 4 posts a month. If you don't have the time to give your blog full time devotion, then plan to write 4 blog posts a month and schedule them to go live one day a week.
This method does not work well if your blog is brand new and you have less than 150 posts made to it. If, however, your blog is drawing in good hits and is filled to the brim with content, you can get away with this schedule without causing too much harm to your blog.
Adding fresh content on a weekly basis lets the search engines know that your blog is not abandoned. It gives the same impression to visitors to your blog. No one wants to really bother with a blog that hasn't been updated in years. Although my old, abandoned blogs on Blogger do still bring in some income, they are not high performing blogs because I do not bother updating them anymore.
Great Amount of Blog Posts
When your blog is new or if you are blogging to earn money, you should post to your blog 3 to 7 times a week. Daily blogs are great because you are showing search engines and readers that you are here, working away. Your blog is not dead or abandoned. Fresh content is always being added. Personally, I do my best to post a blog a day. If I have a day or two when I don't have time to write a blog post, I will, as soon as I am able, go back and post a blog article for the missing days. I like my blogs fleshed out. And, once you develop the habit of blogging every day, it almost becomes an obsession. You have to do it.
Awesome Amount of Blog Posts
If you want blogging to be your main source of income, then you need to treat it like a full time job. Dedicate the hours to it and create two or more blog posts a day for each of your blogs. This is the fastest and best way to build up blog readers. It also gives you fresh content to Tweet and Like each day. Constant fresh content keeps readers coming back each day. The search engines start to love you as you build up your authority on your subject or niche.