Well, as a fellow 6a resident, I have grown many things over the last 15 years. Here are the most common:
Herbs- Rosemary, Sage, Parsley, Thyme, Spearmint, Peppermint, Dill, Chives, Basil, Cilantro, Lavender
Fruit- Apples, Cantaloupes, Strawberries, Paw-Paws
Vegetables- Cucumbers, Lettuce, Beets, Carrots, Tomatos, Bell Peppers, Jalapenos, various gourds, Broccoli
Flowers-Day Lillies, Black-Eyed Susans, Morning Glories, Sunflowers
Ornamental- Coleus and Japanese Maples
Leaf blight took the Basil last year, but everything else turned out just fine!
More relevant to your interests, Phalaris grass grows well. BubbleCat and Frog Pajamas are both correct; everything they mentioned is inconspicuous and grows very well. My MGs take us the whole back fence. Also, any dung or wood-loving mushroom does very well. And more exotic or questionable species are better off indoors.
I hope this helps you out