How to adjust texture after resizing terrain

When I change the width and height of my terrain, the texture applied to it either becomes blurry or pixels get repeated at the edges as the texture isn't applied to the whole terrain. Below is a top view of my terrain with the latter effect.



What settings to I have to adjust so that the texture remains crisp and mapped to the whole surface of the terrain when I resize it?

 

Ok, so for the repeated pixels, obviously I have to change the tiling settings. But for blurry or pixelated textures?

 

You cant add a texture onto a terrain, and then change the terrain size. If you do, it will stretch the texture...

 

That's only if I significantly increase the size of the terrain. But if I reduce it, the texture should on the contrary appear with more details (relative to the size), no?

 

No...your not getting the concept. You should only add a terrain texture AFTER your done sizing the terrain. and then adjust texture resolution to fit the terrain...