Height Blended Tesselation Tearing


I am making my first landscape environment. I use a landscape blend node with heightmap used as a mask. It worked fine and the transition between grass and rock looked nice. Then I wanted to add tessellation. I followed a tutorial ( Unreal Engine 4 - Tutorial Multi Ground Layers Tess - YouTube ) and applied the tessellation and world displacement to my material. It seems to work though I get tearing at the seams and a lot of small flickering overall.

How can I use tessellation with height blending?

Screenshots of material and errors (imgur album):

If you need more pictures or information of the problem just tell me and I will provide it.