Blank slate small urban backyard

I moved into a Philadelphia row home in January. The place was newly refurbished, including the back patio, so there is a roughly 12 ft by 12 ft lot of bare earth in the back yard (I will post up pictures soon). I also have some patio, and walkway space as well as some sidewalk space out front that could make a good place for containers.

Here's the catch...
...because of the nature of my work (grant-funded), I'm not sure if I'll be living here come July.

For that reason, I don't want to grow annuals this season. I'm not really concerned with growing edibles for that matter (not that I'm excluding any edibles). What I want is biomass in the city. I was green space and I would like to do my tiny bit to clean the air.

What are some perennials that are low cost, hardy, quickly establish, and grow quickly? I would like to plant things that stand a good chance at surviving if I can't nurture them past the end of June; for that matter, the plants might not receive any attention after I leave (although I hope I may inspire my roommates, who are staying, to take an interest in this stuff). I guess they should also be at least somewhat aesthetically pleasing to decrease the likelihood that future tenants will remove them in favor of sod.

Any ideas would be appreciated!

Sunchokes! Bulletproof tuber. They like sun and decent drainage. They grow very tall, like a not particularly showy sunflowers (their relative). They spread rapidly - borderline invasive, if you ask me - and will most likely naturalize no matter what neglect they suffer. And you can eat them, if you choose.

put in a thyme lawn.

low maintenance, pretty, and good for bees too.

will also have a steady supply of thyme for keeping skin staph infections at bay.

Thyme oil can sell at high prices too.

Pioneering legumes ,tap rooted weeds(mustard,beets) cherrie pips yada yada
just go crazey dont worry that your not trere to see it!

Bamboo or willow...so many ways to form them into beautiful and living artscapes, useful for biomass, provide a shady and delicate bower for birds and other wildlife and should thrive in PA. There are many types that are not too tall for a suburban skyline and the materials are easily used when trimmed as well.