North American Fruit Explorers mailing list at ibiblio

["Alan Haigh" <alandhaigh@gmail.com>]

In order for a variety to be evaluated hardy in a particular zone it is not adequate to survive an "average" winter.  For fruit trees, I don't think it is necessary for it to be able to survive a test winter either if it is a plum or anything that is reasonably precocious.  If you have to replant every 20 or 30 years, so be it.

 

For a variety of fruit tree to be considered hardy in my opinion it has to prove itself useful, in other words not just surviving but consistently producing adequate crops for a long enough time to be worth the effort.  I would not consider an evaluation reliable if it didn't include at least 10 seasons of observation. 

 

Hardiness evaluations are still going to be a bit murky as borderline zones may allow a certain variety to survive the weather and crop reliably in one soil or exposure and not another.  I have seen variation of survivability based on something as site specific as the depth of soil for instance, like where apricots will survive in a part of my own property where soil depth is approximately 4 feet but not survive where the soil is interrupted by rock outcrop at 2 feet.  I have seen similar contrasts in survivability and cropping consistency created by a wide range of factors not determined by specific zones.