There were two names that instantly sprang to mind. 'Between a rock and a hard place' was the first but I found it too wordy.
The second was 'Hard Rock Farm', however with the Hard Rock Cafe, it isn't original.
Words you can use beside granite could be quartz, feldspar, and igneous. Don't forget you can also go less specific and opt for rock or rocky. Such as Rocky Hill Farm, Quartz Quarters. You don't say what you farm but if it is crops in rows, "Rocks and Rows". It's a shame you don't sell bread, you could have called it "rock and roll".
If you have chickens, "Rocks around the cluck". It depends if you want a fun name or a serious name as well.