I made, edited and added a grass terrain texture for the whole of my terrain as the editor makes it easy to do this. With the terrain editor layer chart, you can add materials and common assets such as trees, rocks, grass, basically things you want repeated in the environment.
Obviously 1 texture on the whole terrain would be boring and with other games you see multiple textures blended everywhere. The editor makes this easy so i made a second texture and tested it. They blend very easily and very well and you can select and paint over the areas you want the terrain to change. The second wet muddy texture i created is for the edges and underneath the water making it look more varied and realistic. So far i have 2 textures for the terrain but i may add more especially for section two where the surrounding will be more raised and perhaps rocky.
The mud texture is not added at this stage because the water texture is not down and you cant see below the fluid surface actor plane, i just tested a small section and i am happy with the blending.