Enable SSL only on main site and disable on all subsites, their front end and back end pages...

I want to enable SSL only on main site and disable on all subsites, their front end and back end pages... When i enter ashleatives.site (the main domain name) it redirects to https://ashleatives.site with the green lock no matter I am logged in or not/in the back end or front end - which is great and works as expected!
Problem begins after a subsite is registered via pro sites or manually, the sub sites' all links both front and back end also lead to https and warn that it is not safe to continue. Please note: I DO NOT OWN A WILDCARD SSL, just a normal one that I only want to use on the main site ashleatives.site