Grasslands in Germany have been producing their own version of garden art since 1992. You don’t mow this grass. Its dried, dead grass. And you do not water it either. The grass changes colour over time (from grass green to a straw-like colour) and drops with gravity. Post 3 years the grass art hardly changes .
You can purchase the following pieces from Grasslands at their website http://www.grassland-site.com/en/home.html. Their work includes spheres and green wall panels as shown in the photos above and below.