This mod enables the Whiterun worldspace's landscape and painstakingly sculpts it up to just below the Whiterun terrain, then adds grass to it. This means that this mod will use your grass textures, meshes, densities, etc, and also means that it should be compatible with pretty much any grass mod. 

The grass will clip with buildings and objects. Skyrim's landscape textures and meshes can only be edited so precisely, and I opted for more grass rather than less clipping. If you want less grass, use the Creation Kit to paint a no-grass texture (I used DirthPath for ease of visibility--keep in mind that the texture won't be seen above Whiterun's terrain, so it doesn't really matter what you use) in the places where you don't want grass. If you want more grass, use a grass texture (I used Tundra01--this one does matter, it controls the grass).

I might be convinced to make patches for the more popular city mods if there's unreasonable clipping, but give it a week or so; this was incredibly, mind-numbingly tedious to make and I am thoroughly sick of grass.

Shown with Voluptuous Grasses, Verdant, and vanilla grass, on vanilla Skyrim with a modified Suki's Preset (NLA).



FAQ:

Q: SSE???!!!!
A: Not until I make the switch, which will not be anytime soon. However, you're more than welcome to port it yourself.

Q: Can you make a patch for [city mod]?
A: Maybe. Like I said, give me some time to recover. That said, I kinda did the hard part, so if you want to make the patch yourself, it should be relatively easy.

Q: Can you make a version with less/more grass?
A: See above.