I've thoroughly scoured all the Vue website, docs and forums over the issue of Solid Growth plants copyright, if there is any restrictions on sharing objects between packages/other people then, I can't find it. Many Vue models are locked from export due to copyright but every plant in the generator can easily be exported without any such problems.
I suppose they are just geometry files(each one different to the next so there's no solid form that someone could copyright and say, 'Hey, that's my model!') so I can't see any problem with that, textures, on the other hand, if the supplied ones are used, might be a different story. Using your own textures on a generated model should be fine. I think.
As I've said before though, if anyone knows any different, I'll remove any links to any SG plants that I've previously shared as there are a few out there under my name.