Limit Footnote Frame Size

I'm working on a book that has a bunch of very long foot notes...there are a couple that take up more than a page.

So my question is how do I keep a footnote frame from occupying more than half of the page?

--Edit--

I've tried setting up a paragraph style that forces every paragraph tto be in a seperate frame, though it is automatic it doesn't look very nice.

I know you could manually pu in a frame break, but I really need an automatic option as the text will likely change several times before the book is published.