Blogs have a peculiar phenomenon; they tend to disappear from the search engine result page as soon as they move away from the home page. If you write evergreen articles (not news updates) you must have noticed, the posts which once brought few hundreds of visitors everyday few months back, now it bring not a single visitor or bring very few. Frankly, we do not know the real reason behind it, but it might be a fact that Google always tries to bring freshness to the search result. To explain it a bit; say you wrote an article one year back “why oranges are orange colored” and you wrote that very nicely which indeed went very successful. Now, some others also wrote about the same topic in their own language and practically the number of such topics has out numbered you and Google pushed you to the 11th result.
There is no known fool-proof method to prevent it, but definitely, some tricks said to be helpful to prevent this fall, at least hinder the rate of fall.
Manually insert links
You can add link to your old post at the bottom of the article highlighting as something like “Other popular articles”. The method is tedious, but works great as you have the total control over what to show. Unfortunately it is not possible if you have large number of posts.
There are several plugins so you can add links at the bottom of your posts to other articles that have to do something with what you have written. This will help the readers to dive into your blog as well as the chance of Gooogle search engine spider to re-consider to position them back increases.
A plugin for WordPress can be Yet Another Related Post Plugin.
Link to the old articles
It is based on link to previous articles from an article. Is the same as directing the reader to related articles, but with minor differences. Typically, the reader will tend to click more on the links in the article than with related with the plugin, since you are recommending it explicitly.
No, we will not repeat anymore because you know it is important to highlight the most read articles .
Recreate new categories
Robots index the posts. So, we will try another method. This is only applicable for blogs with 2000+ posts (for example) and age more than an year or so. Try to create a new category and move the old articles, which almost fetches no traffic now; and allocate those articles to these new categories, sub categories. Google might show error on crawl report for initial few days, but it will disappear as soon Google bot finds the new locations and will send traffic again. Obviously, it needs very careful manipulation and do not do anything very radical. We think touching more than 10% posts will be risky.
We discovered the method accidentally while moving articles for the current category hierarchy.