Weird shadows when baking.

I am getting this effect when I bake the scene, I am using Unity free, but as you can see, the shadows casted aren’t realistic around it.

the rocks, so far a lot of them have a weird shadow like this
or something unrealistic.
How do I solve this?

you have to set objects you want to lightmap to static ( make sure its checked ) , then bake the scene - The whole scene