Get pots, plant in them. Drive out in the middle of nowhere, get some dirt, and **** in it. (Look up the used of urine in a garden.)
Also, look for patches of land near where you live that you could somehow bring water to, and plant there.
I live in an apartment. My younger brother had been practicing what he calls "pirate gardening" (called "guerrilla gardening" by anarchists - google it) and that is gardening on any land that isn't yours. I planted a garden on the apartments property after clearing out the rocks and trash, and my neighbors have all complimented how I made it look and the landlord hasn't said anything but jas weedwhacked around my plants to obviously he's ok with it too.
If you're gonna plant now, make sure to check that its plants that can grow this time of year. My side of WA is said to be similar to CA for crops, so try beans, peas, radishes, turnips, brocolli, kale (KALE!) And whatever else you find in a search for "fall gardens."
You may also benefit from looking up wild foods. A lot of what are considered weeds that grow between the cracks in the concrete are among the most nutricious plants in the world. Check out the edible plants section on this forum.