why does my grass or any foliage i place turn to a 3d “+” ?
sorry i am very new to this.
It’s missing the material
As I see from the pic you are using my foliage starter kit? 
Make sure that you have correctly added it to your own project (the video in my thread), because otherwise you will lose some references (e.g the texture in the material) -> that’s why it gets displayed with the default texture