Hey Byron J
You said to be more specific, so I’ll be more specific on a level of knowledge that I think we (other people viewing this thread) can simply understand.
For an example of what I’m talking about I will use blyx japonica, since that is the plant I am currently looking to purchase for another scape I am conducting…
Blyx japonica naturally (and to my experience seeing it) grows in sloping streams, sloping streams is where there is a small stream of water between two small hills, or waves in the earth as I call it myself. Usually this is in a tropical to sub-tropical environment that these plants grow in.
Here is an image of a stream that resembles what I am talking about. The soil Blyxa Japonica grows in is generally rich in iron, and other mixed nutrients. The streams it naturally grows in are slow moving, to medium moving waters. Now as for the soil it grows in, this particular plant I picked out for my example since its common and at the time was on my mind, grows not in a clay like soil, or a sand rich soil, but a soil that is just, regular nice soil. The soil is difficult to explain as it is generally untouched by humans or man, it is porous and allows the roots to get good water flow (so to say) and air flow. Again this is where the water column nutrients also comes into play for the plants health. Usually this dirt is a brownish color (as dirt usually is) mixed with old decomposed leaves that have caught up in the plant adding extra vital nutrients to it to assist the growth of it. Fish is a different story, but it ends up providing vital nutrients as well.
In the home aquarium Blyx Japonica is used in common and difficult to explain aquascapes such as this one
It is a common and mostly easy plant to grow in my own experience, and its fun if you like maintenance. I won’t get into the plant care, and such since this is about the substrate it grows in. The substrate that is most common and most efficient for blyx japonica to grow in, in the home aquascape is as previously stated ADA aquasoil, usually of any kinds. With a layer of powersand as this always helps it jump and thrive. It can grow in sandy soils but it will slow the growth of it, I personally have not done experiments with this particular plant in any way as I just haven’t reached this on yet.
I hope this answered some of your questions Byron that you had about this plant and the soils that some plants grow in, just for the record I didn’t particularly pick this plant out because it grows in a soil that isn’t sand that to me would be an unfair or unjust thing to do if you get me.
Hope the best.