Any advice on cultivating the local wild fruit?

I am an avid gardening living in northern MN (growing zone 3) and I want to grow fruit such as blackberries, gs, elderberries, and so forth. The problem is that very few cultivated varieties can grow this far north. I was thinking that to overcome that I could attempt cultivation of the local wild varieties via vegetative propagation techniques. The advantage of this would be I could not only get the fruit I wanted but also the plants would require less care than their domestic counterparts in order to produce. I know that they won't make as much fruit as the cultivated types and it will taste more tart, but something is way better than nothing. I would like to know if anybody out there has done anything similar to this and/or do you have any advice?