Hello. In the absence of more knowledgeable replies, my experience has been that it's best to get them into the ground sooner, rather than later. Major frost/cold would be about the only thing that would make me pause. Have been planting/transplanting cobnuts, jostaberries and apples into soil which is too muddy to work, but strangely feels better than it was during the freezing temperatures of last week when it was dry!