"Good morning, here's our rooftop garden on the Gowanus side of Park Slope. I guess the space is about 15 X 15, and planted with (among others) a butterfly bush, tomatoes, clematis, herbs, mesclun, morning glories, elephant's ear, dahlias, marigolds, asters, and a weeping cherry." [more below]
Everything but the cherry was from seed or 6 inch container size. We put up four poles for plants to climb on and to a hang a sun shield and curtains as you can see.