How to transition between mountain and desert material? [duplicate]

I'e looked at many tutorials for creating desert mountains / deserts individually, but I'm trying to make a scene with a mountain in an actual, realistic desert, and I can't seem to match the materials correctly.

I don't have a direct screen shot (on another computer now) but basically I followed this tutorial to create a desert mountain https://www.youtube.com/watch?v=sxTc1rAd7Hk and basically everything was good following the tutorial, my mountain looks about like the one in the picture (taken from the video)

But now is where my question comes in: how can I actually combine this into a desert scene? As you can see in the picture, the material edges of the mountain mesh doesn't at all look like sand, and if I just put this on top of a desert like this:

then it obviously wouldn't at all look realistic, obviously.

I tried to just blend the two materials together using UV textre painting and (as an alternative) gradient masking in the cycles node setup (to basically just make a circle mask around the mountain, gradually fading into the sand material), I don't have a screenshot now, but basically: it didn't at all look realistic.

So if anyone knows some alternative way to combine the mountain material with an actual desert material, or someone make the desert match the mountain (other than just basic blending), that would be good.