what are the laws for growing on rental property

We would like to know the rules and/or laws of growing on an rental property. We have been living in a mobile home park for 7+ years and this is the third year weâ??ve grown here. But this year my husband was only growing one small plant, while watering, the water seeped under the back fence to other property and the property manager was in town and noticed it. He looked over the fence and saw the plant, he came around to our property, went behind a gate in the yard where it was and pulled it out of the ground and left it there. I have been searching, calling everywhere trying to find out what we can do, my husband believes he was truly vandalized and his civil rights were violated. Need answers, can you please help!!!!!!