One thing I recently implemented on my WordPress blog is to close comments on posts older than 30 days. After 24 hours, I noticed my spam comments has dropped dramatically to zero. That’s a good thing.
To close comments on posts after x amount of days, all you have to do is access your WordPress Dashboard > Settings > Discussion page. Look for the option saying “automatically close comments older than x days.” Here’s a snapshot of the page.
Just check it to turn on the feature. Supply the number of days that you want the comments to be turned on. Comments will be turned off on posts older than x number of days that you’ve provided. Simple enough. This is just another tool to help lower your blog’s spam comments. It certainly did on my blog.