Set a minimum number of characters in a Text - Long field

The Text- Long function includes a field to set the maximum number of characters allowed. I have come across a use case for the ability to set a minimum number as well.

I have a form on which a user is supposed to write an "essay" that counts toward one of their annual job goals. The department sponsoring this form wants the essay to be at least 250 words long. Of course, I know words and characters are not the same thing, but having a minimum might still allow for more control in the field in this use case.