We had a relatively mild winter in Edmonton this year with a few cold nights into the -35c range in December 2012 but overall no too bad. We also had good snow cover through the winter right through till the mid April point and as such the vine received good insulation from the cold. At the end of April Mother Nature flipped the summer switch and we hit +31c in the first week of May and the vines are a bit advanced so far heading into June.
I left the St. Croix and Acadie Blanc on the trellis this past winter year to see how it would make out without laying the canes down on the ground. Not the best year to make this test as it we did not have the extreme cold snaps nor prolonged cold.
Looking at the emerging shoots on the vines this year I see some amazing results. The St.Croix (now coming into 6 years old) came out great again and has two clusters per shoot on nearly every primary shoot, even secondaries produce with this variety. Some of the flower clusters this year are huge and I attribute this to the health and maturation of the vine. The acadie is only in its second year since I moved it and it has 1-2 clusters per shoot on each shoot. This is not supposed to be that hardy of a vine but it has no problem with the Edmonton winters, especially if the canes are layed down to the ground. No need to bury them if they have a bit of snow cover. The Evangline also look good with decent survival rates considering I moved the 1 year old vines in early summer. St Croix photo below;
The other surprise is an Edelweise that I had planted and dug out and moved into a large planter pot. It had not been performing well so I dug it out with plans to move it or throw it out. However as summer passed I did not have a good place for it and was not inclined to make room for this "underperformer". Having said that, I left it in the pot in the garden and forgot about it and there it stayed over the winter and to my surprise not only did the vine and the otherwise exposed roots survive the winter - the emerging buds are also fruitful (which it has rarely been). I'm going to grow it in the planter and see how that works this summer. See Edelweise photo below;