Procedure trigger "when jumped on"

So, I'm trying to do a mod where I can make a zen rock garden: I made a tool (rake), that when used on sand, replaces the sand with a block I made which is sand with lines.  That's fine.  The thing is, I want to make it so that it works like farmland, in the sense that when it's jumped on, it turns back into sand.  I don't know how to make this happen--specifically, how to make a procedure trigger upon a block being jumped on, if indeed it's possible using MCreator.  Help?