- Get a Better WordPress Hosting
Comments are resource intensive. Each time a user submits a comment on your WordPress site, your server runs a PHP script. If multiple users are submitting comments at the same time, this could slow down your site. Try a WordPress hosting provider like WPEngine for betterment.
- Use Comment Moderation Instead of Captcha
Instead of using CAPTCHA, you should enable comment moderation on your site and manually approve each and every comment. Comment moderation will not only allow you to block spam, it will also provide you a chance to interact with your users more often.
- Allow Users to Subscribe to Comments
You can provide users a chance to subscribe to comments on your WordPress posts. This way they can get immediate notifications when there is a new comment. This will significantly increase your pageviews and number of comments on your website. Your users will find discussions on your site to be more engaging.
- Notify Users on Replies to Their Own Comments
You can easily allow users to subscribe to their own comments. This way they will only receive a notification email when someone replies to their comment. This could develop a highly engaging community around your blog if you make it a habit to reply to most user comments on your site.
- Show Newest Comments First
By default WordPress shows the newest comment at the bottom of the comments list. This can be easily changed in WordPress, simply go to Settings > Discussion and scroll down to other comments settings section. You need to select newer from the drop down menu.
As you noticed, the enumerated ways above are consists only of five (5), you can view the rest of them at Ways to Get More Comments on Your WordPress Blog Posts.