I have a number of seedlings bred from John Davis and L83 currently living in five gallon pots outdoors. These selections are from 2007 crosses and so will be two years old this Spring. I chose to leave these plants outside during the recent cold snap, unprotected, to see how they handled the cold. Crosses involving 'John Davis' and L83 were made to improve Winter hardiness (and disease resistance) and I figured it was time to start testing them for this trait.
I am happy to report that all of the L83 seedlings and all of the 'John Davis' hybrids came through with no damage whatsoever. Canes are green and healthy right to the tips. I recognize that compared to the mid-West regions, a cold snap like our recent one (a week of night temps down to 7 degrees F) isn't much of a test, but since I have seen significant damage to other seedlings (and some appear to have died completely) this tells me these hybrids have inherited some degree of freeze tolerance.
Shown above is a cane of 'Golden Angel' X 'John Davis', one of the pale yellow selections from this seedling group. As you can see, not only did the canes survive without damage, even some of the foliage that grew in late Fall stayed on without any damage! I hope that's a good sign.
PS: today I am processing seeds in preparation for sowing. Next is 'Midnight Blue' X 'Veilchenblau'!