We are currently sitting at about -40F (-40C)! We have been in a cold snap for almost a week and have about that much longer to go before warmer weather returns. With a few feet of snow on the ground, some of our smaller bushes (and all of the terrace vineyard vines) are protected from the majority of this cold. However, we have a number of taller bushes and small trees that are taking the full brunt of the cold. While we have seen -41F at the farm in the last 10 years and know which of these bushes and trees should make it through the cold with little to no damage, there is always the question of how well prepared they were for winter. Those that suffered from too little water early in the summer or too much water late in the summer, may be more susceptible to winter injury in these temperatures. Other bushes that are not so hardy, such as black currants and our unnamed, seedling aronia bushes, will likely die back to the snow line. That still leaves plenty of wood below the snow to leaf out in the spring and rejuvenate the plant. There will be a good amount of pruning needed on these plants next summer. It is always a gamble with plants that aren’t completely hardy at our location, but -40F only comes about once every 10 years, so in the intervening years we can get quite a nice crop.
The vineyard is all nestled in, but there is still a risk from cold periods like our current one if the cold lasts too long. Snow is not a perfect insulator, so it slowly loses heat from the ground over time. The vines that are planted out on the terraces should be fine, but we have a large number of potted vines that are in pretty dry soil at this time. They are more susceptible to damage. We also have a couple of Vitis vinifera (European grapes) in pots that are not very cold tolerant (when compared to others that are hardy to -30F to -40F; -35C to -40C). These varieties include Gewürztraminer and Müller-Thurgau. The roots on these vines will probably suffer some significant damage and the vines may die outright from the cold. This is a big reason why we don’t focus on the grape varieties you would typically associate with wines. On the other hand, great strides have been made in recent years in breeding cold-hardy (still a relative term when growing them in Interior Alaska) grapes that also make quite acceptable wine. Something that a lot of people don’t realize, but can be very important when growing grapevines in the far north is that one of the factors in hardiness is the duration of cold temperatures. Even the hardiest vines will die back if the cold (maybe not even severe cold) lasts too long. This coming spring, we will find out if the vines we have planted on the terraces experienced too many hours below 0F (-18C). Fingers crossed!
The cold may also impact our cut-flower trials that we started last August. Two years ago, we planted delphinium (known to be fully hardy in Interior Alaska) and campanula (Canterbury Bells) in a raised bed and they both survived the 2022-2023 winter very well. However, it only dropped to -22F (-30C) in January. This past fall, we planted more campanula, along with several other flower varieties (sweet William, feverfew, rudbeckia, and yarrow. The yarrow will do well, as it is native to Interior Alaska, but the others probably won’t make it. Nevertheless, we won’t know until the snow melts and the beds start to thaw in April. Yet again, fingers crossed.
There are a few benefits to the cold! It usually reduces the bug population for a summer – never a bad thing. It also makes the tourists go home, at least for a few weeks. We then can walk through the stores in relative peace. And while that may sound a little selfish, anyone that lives in a major tourism area can attest that area residents can always use a little respite from the pressures of tourism to reinvigorate them for the upcoming tourist season.
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