How to blend Texture2D colors using shader graph

For clarification, I started using shader graphs very recently.
Essentially, what I am trying to accomplish is blending my Texture2D colors together so the transition seems smooth.
Some background info. I am procedurally generating a color map. I have a plane which has a material I am editing through script. My Texture2D has “Material” and “Source” set to the material I use on the plane, So I can reference my Texture2D from the shader graph. For the mesh (which I am generating the heightmap), I have a material which uses a shader graph, which I am currently trying to understand. For the script I am generating the map, I have my regions and height set to: Sand, 0 | Grass, 0.7 | Snow, 1
Currently, my material on the mesh that has the shader graph looks like this:


For some reason, the output (as you can see on the Sample Texture 2D) is not smooth at all, and currently looks like this:

As you can see, for some reason, the snow is between sand and grass (colors are also opposite).
Without splitting the G value on the shader graph and inputting it as the Sample Texture 2D’s UV, my mesh looks like this (which is just the Texture2D ontop of the mesh).

If I only take a position node and split it and take it’s G value and input it as the base color, I can see some sort of height map.

How can I accomplish blending the colors together on the Texture2D using a shader graph?
Again, I am a complete beginner to shader graphs. If there are any further questions, ask and I shall answer.