Another year in the books, as they say. We were very focused this season on relocating the vineyard. After discovering that terraces greatly increase the soil temperature on hillsides here in Interior Alaska, we began planning how to move our 150 or so grapevines from their field location to a series of terraces we had built a number of years ago. Those terraces had been planted with currants, gooseberries, and peonies within the last decade. Since that time, the terraces have begun to slump and we kind of ignored them other than in the fall during currant and gooseberry harvest. The peonies did not like that location from the very beginning. While the soil was much warmer, it was also rockier – and that tended to damage the delicate flower buds peonies are known for. So, why not repurpose the terraces!
Starting as soon as the snow melted, we began pulling hundreds of willow, alder, birch, and poplar saplings from the terraces. We targeted the top two terraces for planting this year. We hope to double that number next year, but there are so many saplings that it is slow going. By late summer, we had augered the post holes for the trellises on both terraces and had begun planting vines. We were able to fit 20 vines on each terrace, spaced 6 ft (2 m) apart in the row. The terraces are 7 ft (2.2 m) wide and about 30 inches (0.75 m) tall at the nose. With these dimensions, the terraces intercept quite a bit of sunlight during the early summer, with soil temperatures reaching 75-85 degrees Fahrenheit (25-30 C) by early July at a depth of 8 inches (20 cm). That may not sound unusual, but here in the cold north, the normal temperature at that depth mid-summer is about 50 Fahrenheit (10 C). In fact, as part of our ongoing experiment with grapevines on the terraces, we dug holes for every potted vine and left them in the holes for almost the entire summer. The difference in root growth and plant vigor between the terraces and the field was quite obvious.
By the end of September, we had installed the posts and the vines were hardening off quite nicely for winter (see picture above). Our first freeze came on October 9th, about 2 weeks later than expected. What we discovered next was a bit surprising. We had installed two thermometers on the second terrace the previous summer and noticed over last winter, the temperature at 8 inches (20 cm) never dropped much below 30 F (-1C). However, this year fall was on the dry side, with little snow falling until mid-November. That combined with air temps below freezing for extended periods of time quickly removed any remaining summer heat and the soil temperature at 8 inches (20 cm) dropped to 17F (-8 C) by the end of November. Grapevine roots of some species are rather sensitive to cold, with Vitis vinifera suffering substantial injury or death below about 23F (-5 C). Other vines we have, including pure V. riparia and V. amurensis, have much hardier roots and should not be injured at this temperature. This finding does suggest a limit to the use of terraces on the farm for growing cold tender plants. And we are not out of the woods yet. As of today, the terraces have again dropped below 20 F (-7 C) due to a recent cold spell. We will find out next spring which vines are more susceptible to root damage!
Speaking of peonies, we continue to move them from the terraces and other raised beds we have to a larger field location. Currently, we have about 700 planted out in the field with varying degrees of success. To augment the peonies, we upped our production of other flowers this year, selling to a local florist throughout the summer months. Next year we plan to double or triple our flower production as we open up more areas to plant them. The major issue with expansion continues to be the lack of water. Our 2000 gallons (7560 l) of water we capture from melting snow in the spring goes quickly, and it is usually early August before the summer rains arrive. We will likely be hauling water in to supplement.
Next year may also be the last year we hold our annual plant sale. This will be our 15th May plant sale and if the recent trend of decreasing sales holds, it will not be economically feasible going forward. We started the plant sale in 2009 as an early season source of income for the farm, but the timing has always interfered with the completion of other important chores. Moreover, with the increase in flower production, we will need more indoor space for flower seedlings – and there isn’t much space to begin with. So, something has to go. Shifting away from growing seedlings for the plant sale will allow us to focus on flower sales and our ultimate goal of making wine from the vineyard. Somewhere in between, we need to drill a well!
The short-term forecast is for a pretty chilly January and early February, but a nice warm up in March and April. Then it will be time to check in on the vineyard terraces to see which vines survived and which ones will need to be replaced. Stay tuned!
