Do your plants stop attracting wildlife after a certain amount of time, or will they keep attracting until they are harvested? thanks for any help.

No, attracting plants don't expire.  As  long as they are at the correct stage, they'll attract.  If something attracts when fully grown, it will continue to attract until it's RTH.  If it attracts when RTH, it will continue to attract until you harvest it.

Your Easter egg plant will "expire" after two weeks, though, if you don't complete it, if that's what you mean?   If it becomes RTH before you complete it, you can't then add more to it, and you won't get the pot when you harvest it. 

thanks Tracey. I was just wondering because I have 2 RFH Luna Serenas in mine, attracting badgers, and they've been planted for quite a while. appreciate you.

They're fine, they will keep attracting for as long as  you keep them :)

Rebecca, if you want to attract more badgers, then I would harvest one of the lunas because both attract more hedgehogs.
You have the RFH Sundragon Herb which can work as a deterrent but only for one hedgehog.