Reddit reviews Guide to Flowering Plant Families

I agree with /u/whyen0t -- taking a class is really a great start! Beyond that, I would recommend getting a dichotomous key for the flora in your area and starting to familiarize yourself with different plants you see quite a bit. Often, there is a "Guide to the Families" section in the beginning of a floristic guide that can give you a really good sense of the big characteristics that define each family. Just googling a guide to the families brought me to this one: http://www.amazon.com/Guide-Flowering-Plant-Families-Zomlefer/dp/0807844705/ref=sr_1_1?ie=UTF8&qid=1415690844&sr=8-1&keywords=guide+to+plant+families --I don't know anything about it personally, but it seems to have good reviews!

My beloved plant systematics professor in college assigned Guide to Flowering Plant Families by Wendy Zomlefer, and these many years later, it is still one of my most frequently-consulted books. Not only is the book full of information on 130 plant families, the line drawings are fantastic, too.

Like others have said, learning what characteristics plant families have makes plant I.D. so much easier. If this is something you really want to learn, I'd recommend a book like Wendy B. Zomlefer's Guide to Flowering Plants or Practical Plant Identification by James Cullen. Both of those should give you a rundown on common plant family characteristics and help you narrow it down at least to a family, if not a genus. Being able to accurately I.D. plants quickly is mostly practise, though; the more you do it, the easier it gets.

Though, because you don't think it's a native plant, once you have a rough idea of what it is, you can look at ornamental plants that will grow in your zone.