Early to mid spring is the absolute best time to do most cutting IMO. In the spring about any cutting placed in soil, if kept constantly moist, will take root. I've had good luck doing this with lilacs, and not even using root hormone, though that would likely improve success rate. When the temperatures warm, it is very difficult to get woody stem growth to root. Fall works equally well here in S.C., but am not so sure that such would be true in your harsh winter climate.
Eclectic gardening style, drawing from 45 years of interest and experience. Mostly plant in raised beds and containers primarily using intensive gardening techniques.