No, but you can overwinter things like spinach and kale for a very early spring harvest before they go to seed. And, there's lots of veggies you can plant now for a late fall harvest, if you have beds available. I'm guessing you're in southern Ontario (aka what we Prairie folk call the Florida of Canada).

Thanks :) Well, southeastern Ontario, south of Ottawa. I do have space available in my garden for some planting, what do you suggest?

I'd suggest some spinach.

Yes, spinach is good. Also any kind of fast-growing Asian green like bok choy, tatsoi, gai lon. Other good choices are kale, cilantro, dill, radishes, chard, leaf lettuce. You may be able to pull off beets. Keep the soil moist and shaded to encourage germination.

I suggest a hoop house too. -30C is -22F, I don't think anything uncovered can survive that, unless there is good snow cover.