Hi, Fred -
When I lived in northern Wisconsin hazelnuts grew wild. Small but so tastie. I harvested but didn't have to plant so I know nothing about it. When is the best time. We are still getting snow and freezing nights here.
I always tell folks you can plant any time the ground isn't frozen, and the soil isn't so saturated you run the risk of compacting the soil by digging. Hazels are so hardy they barely go dormant, and they start their fertility cycle really early in the spring. I say plant as soon as you can!
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