I guess what planting zone one lives in helps define "big leafed" plants. When I lived in New Orleans (zone 9), my plantains, bananas, castor beans, and elephant ears were the largest leafed plants I had. Now that I'm in the mountains, my vegetable garden sports the most 'tropical' looking large leaves with different zucchini squashes. I grew those in the south for the same reason... multi-use veggies and beautiful foliage. It's squash season here now (August), and the plants... along with their bounty, are in their glory.