Is the apartment complex liable for my injury?

I fell in the grass because I stepped on a hole that was covered by grass at an apartment complex. Sidewalk ended at parking lot but if there's a car parked there, you have to walk across 3 feet of grass. You can't see the hole because grass isn't cut real low. I sat there for 5-10 minutes before I could get up. I can walk but if I step at a certain angle, there is pain.