Something I’ve done and still try to do if I can is to send an email to those leaving comments for the first time.
When someone comments on my site for the first time I send them a thank-you email.
I say something like:
“Thanks for the comment on such-and-such post. I don’t know if you’re new to the site or if you’ve been reading for a while and this is your first comment but either way your feedback is apprecated and always welcome.”
This helps them feel noticed and part of the community; like someone is paying attention to what they have to say.
