Trying to steal Vray's thunder.
I'm gonna wait for Steam version
Blender Guru is selling an amazing asset package The Grass Essentials, which includes some of the best samples of vegetation for your 3d needs.
If you’re working with Blender and trying to build some sort of natural environment, you definitely need to have a look at The Grass Essentials. It’s a relatively new asset package, which includes some amazing grass assets for use in games and in simple 3d scenes. Essentially it’s a pack of models and particle systems, which help to build incredibly awesome scenes. Overall there are 15 Species of Grass, with up to 49 model variations for each. A total of 471 grass models and 15 species of weeds, which make the grass even more realistic.
The coolest thing is that this physically modeled grass renders faster and is better optimized for usage in games and 3d scenes. You can easily customize the whole thing and figure out the best look for your project. You can just import all the assets into your project. There’s a little tutorial from Rob Garlington included into the package to help you work with the new assets.