Sand and Gravel?

Is it Possible and has Anyone done a Mix of Sand and Flourite for a Planted tank? I'm about to start Cycling my 90 gal and was thinking I would do the front half (foreground) in Sand and back Half as Flourite to grow plants?

Good Idea? Bad Idea? Suggestions?

Also The only plants I used so far are Java Moss and Java Fern so this will be new to me.

THANKS!