Well, this is maybe easier than you think. As a quick and not sooo dirty solution you can do the following.

Create a Carex plant in a scene and a grass patch - default or whatever you have. Then select the grass patch material and copy it, select the Carex and paste the copied material onto the carex. Then open the plant editor and change curlyness and flexibility to your needs and you have a single grass plant that you save from the plant editor as your own new species.

The other solution is - I double checked it now - Incredibly Lush Grassy Places that contains minimum two single grass blades and a weed. Or Incredibly Lush High Grasses that is made from single plants anyway. Both, as many other packages, available at Cornucopia3D.

One day your ship comes in - but you're at the airport.