Epsom Salt for Ferns?

Last night I finally shared the liver/gallbladder cleanse with my Mother-in-law. She was the last in my family because of the medical background. (My Father-in-law is a Dr.) She was SO interested it made me ashamed I had waited so long to tell her. She actually said it made perfect sense to her.

But, she told me you add Epsom Salt to the water when watering ferns to obtain that lush, deep green color. You live and learn! I had never heard of that, but all my mighty ferns got that early this morning.
We live in the "Deep South" where, this time of the year, you might as well be living in the Amazon---high humidity and hot, hot!! The kind of weather ferns thrive in and love!!

Just thought I would throw this in............