You could mix any type of substrate with playsand if you wanted too.
My experience with playsand is mixed...
I started my 55g as a low tech "Test" tank to see if I could handle the planted tank scene. Turned out I could and 1G later I'm done buying the equips, but I'm left with the playsand.
While it can grow plants pretty well, I HATE IT. you can see every little piece of crap from my pleco and you cannot pull plants without stirring up debris I would advise against it at all costs.
Not because it is bad for growing plants quite the contrary it is very good, but because you can hardly do maintenance with playsand.