Cats love grass... any grass... It does not need to be that special stuff sold for kitties. Also... Regular lawn grass is better, as nibbling on it, does not kill it. Grow the same type as grows well in your yard. Get a small bag of lawn seed, preferably one that is not treated with chemicals. Place some soil in a tray or shallow dish. Sprinkle a nice amount of the seeds on the soil, and lightly brush with the palm of your hand, to work the seeds slightly into the soil. Slowly moisten the soil, so as not to have the seeds float. Keep the soil moist... Also.. Start the lawn grass outside, to get the full benefit of the sun. Once it is nicely growing, and mature, then you can bring it in for the kitties.