Francis, I did the exact same thing last year, in late October or early November! After I had finished canning last fall, I had two bulbs of garlic left from Albertsons, just your run-of-the-mill softneck garlic. I broke 'em down into cloves and actually planted them in frozen ground. When I tried to break the clods down with my bare hands, it hurt like nobody's business, so some of them were simply shoved down between clumps of frozen dirt.
We hit a two-week warm spell in November, maybe warm enough to help them set roots, but I'm not certain. This spring they were the first plants up, the only sign of green in the whole neighborhood. I got enough garlic from those two bulbs to do my canning this fall and, if I choose, plant some cloves again. They took very little space, and I bet a person would never have to buy garlic again if this was done each year. They really last a long time in the fridge. Pretty nifty!
"Imagination is more important than knowledge." -- Albert Einstein