What you are looking for is an Appearance Asset - not a Material per se. Your installation has both a Material Browser as well as an Asset Browser, which includes Thermal, Physical and Appearance Assets.
(1) Create a New Material, (2) rename "New Material" it to "Grass" or whatever you prefer, (3) switch to the Appearance Tab, (4) press the "Replace this Asset" button is to open the Asset Browser, (5) type "Grass" in the Asset Browser Search Bar, select one of the many Appearance Assets found, and then (6) press the little blue two arrow button next to the Asset Name to "Replace the current asset in the editor with this Asset".

End Result:
