Yes it definately will...
What I did was to work the sand into the flourite with my fingers so that it fills the gaps between flourite chips. Then when you have it pretty much "filled" add another layer of sand over it.
When you plant in it you will stir up some flourite also but if you want it covered just add scoops of sand after planting and you are all set.
I have been in and out of my substrate getting the final scaping done to my likes and I am going to wait a few days to be sure that I am sure
and then I will add a final sand layer and let it grow.
I really like the sand look and I am happy I decided to try it... I was worried about it being to "compact" a substrate for fine roots but after uprooting a few plants for friends and also for rescaping the tank the roots obviously have no trouble whatsoever ! They almost root TOO good... LOL
Even the Cardamine lyrata which has very fine roots has done very well in sand...