making the functions inline sounds like an excellent idea...however, I didn't quite understand this...
"The work that a class does should be internal. You should tell the plant class "Grow(-- ground parameters -- time parameters -- etc --)" and the class itself should check to see if it can or how much."
I was planning on having the plant class get information from the ground class, and maybe other classes, depends on what I think of, and then do the math for if it can grow inside the plant class. But I need that data from other classes, and other classes, which haven't been mentioned or thought of yet, but will exist, will also need to get information from the plant class, and the ground class, and other classes. Obviously some data will be private...keep the suggestions rolling, though (:
