Yes. There are quite a number of import options available.
Yes. If the model is created correctly. Lots of stuff involved in that. Not difficult but you need to learn how to use it just as you need to learn to use any tool.
You would create Components for your plants which can be unique or multiple. There is then a scheduling feature that will list out how many of each there are in your drawing. You can also add attributes like cost to end up with a spreadsheet like list.
Just be aware that Sketchup is a means to an end and not dedicated to any one industry. So you will not be able to do what you want out of the box. As @DaveR has said, it’s a tool you have to learn to use.
I appreciate your comments! Currently working through the process to determine if Sketchup Pro is the right tool for my landscape business and design needs. I like how this product can create 2D documentation, is relatively affordable for the features it offers and has a strong support network for learning and trouble shooting.