Tag: cold injury

The Big Chill — We Felt it through the Grapevine

It takes years of hard work to establish a vineyard, but only one bad night to lose it.

A week ago Wednesday, I thought that night was upon us. With subzero temperatures in the forecast, it seemed as though we might have been on the verge of losing our little hobby vineyard, which has been the focus of so much of our time and energy for the past four years.

To jump to the end of the story for just a moment, we spent a long day working in the vineyard on Thursday and a long night of checking the temperature on an hourly basis and begging the climate gods to show some mercy. And when I climbed out of bed Friday morning, I was feeling much more optimistic. We won’t know for sure until later in the year, but I believe that our vineyard survived, though not without some degree of injury to the vines.

Oh, yes, I am truly freezing.

Oh, yes, I am truly freezing.

We had known for several days that severely cold weather was on the way, but it had seemed as though it would be manageable. We monitor a number of weather services – WxRisk, Weather Underground, and the Weather Channel among them – and the latter two provided forecasts that varied daily. (They also vary between each other. Sometimes I pick the one I like best and lull myself into a false sense of security.)
So, the outlook for early Friday morning looked very different on Wednesday than it had only a few days earlier. Negative five degrees had been scary enough. But I was really surprised to see forecasts that warned of temperatures as low as minus 13 degrees Fahrenheit.

Now, our vines can do just fine in freezing weather, and they’ll even manage through sub-zero temperatures. At some point, though, you can expect injury. Everything I’ve read – I’ve never experienced it, but I’ve done a fair amount of reading – suggests that at negative five degrees we should expect to lose at least some of the buds that would produce shoots and grapes in the coming growing season.

And at negative 13?

Well, the damage could be catastrophic. Buds are more sensitive to the cold than trunks and canes, but only by a few degrees, according to Virginia Tech’s Tony Wolf, who was good enough to put out an alert Wednesday with lots of information about the effect of freezing weather on vines.

Losing a significant number of buds and part of next year’s harvest would be bad news. But it’s one thing to lose part of the crop and quite another to lose the entire vine. At some temperature, the scion – the actual vine, which is grafted onto rootstock – could be killed. If that happens, there’s little alternative but to replace the vine.

That would be disastrous for anyone, and my heart goes out to commercial vineyards that might have lost either a substantial portion of the 2015 crop or some part of their vineyard. For them, it’s everything. For us, it’s a hobby, not our livelihood, so it would be incredibly self-centered for me to complain too much about our potential loss.

Having said that, though, the prospect of losing vines hit me on a very personal level. We’ve spent more than four years getting to this point, and I feel like I remember almost every minute of the hard work and sacrifice.

Vines hilled up with mulched leaves and grass.

Vines hilled up with mulched leaves and grass.

But forget, for a moment, about the time we spent taking classes, reading and talking to vineyard managers to learn everything we could about viticulture. And forget about the cash outlays. Let’s also put aside the hours of physical labor that went into establishing the vineyard. (Well, not too far aside – I can still remember a day last summer, working five hours with a backpack sprayer and thinking I was just about ready to die by the time I finished.)

As important as all those things are, what matters most to me is the time – the number of years it takes to order vines, plant them, and nurse them through to their first harvest. We all have only so much time in this life. And that means we get only so many chances to get it right.

So yes, we could start over again. We could order vines, but we wouldn’t be able to get the vines we want this year, so we wouldn’t be able to plant until the spring of 2016. And it would be another three growing seasons before we harvest again. That would bring us to the fall of 2018, which seems like forever.

We did have a couple of things going for us. First, we had a couple of weeks of freezing weather leading up to the big chill, which helped harden off the vines. That meant they should have been able to withstand lower temperatures than would have been the case if the deep freeze had hit all at once.

Second, we had a blanket of snow on the ground. Snow has an insulating effect, and if it’s deep enough, it can protect the graft union, where the scion is joined to the root stock. In our first two years, we had hilled up around the vines, creating a mound of dirt a couple of inches above the graft union to provide the same kind of insulating effect. This year, with the harvest and all of the time and labor that goes into fermenting five different varieties of wine, we just didn’t get to it. Lesson learned.

Third, we’ve planted varieties that are reasonably cold-hardy, including Cab Franc, Petit Verdot, Petit Manseng, and Viognier. The exception is Merlot, which is much more sensitive to cold injury. The Merlot is also the youngest of the varieties we planted and therefore the least able to take winter’s punch.

For all that, though, we were pretty worried. By the end of the day Wednesday, the Vineyard Goddess and I had decided to spend Thursday doing everything we could to protect the vines. Our plan was to use mulched and partially composted leaves and grass to hill up around each vine, in the hope that we could insulate the graft union to the point that we could save the vine, if not this year’s harvest.

We traveled to Afton Wednesday night so that we could get an early start the next morning. Sometime around 8 a.m. Thursday we made our first foray into the vineyard. It was about 3 degrees above zero and the wind was blowing. I was colder than I think I’ve ever been in my entire life, and we went back inside to add a couple of layers of clothing, have a cup of coffee, and wait for the temperature to reach a more civilized 6 degrees or so.

Another shot of the hilled over vines

Another shot of the hilled up vines

By 9 a.m., we were working in earnest. Over the years, I had dumped a large volume of leaves and grass clippings into a heap on the other side of our property, and we had a very large pile by this point that was just waiting to be repurposed. I used the front-end loader on my tractor to haul them into the vineyard where the VG mounded them around each vine. Here and there we added some snow to pack the mulch down, but mostly, we relied upon the organic matter to insulate the vine.

The overnight temperature readings were somewhat milder than the forecast, but they were still pretty severe. At 7 a.m., the temperature hit minus 6.1 degrees, according to the Weather Underground station closest to us. I would have preferred to have our own weather equipment in the vineyard, but this station is not only close, it’s also at the same elevation as our vineyard, so I expected that the readings would be very close to what we would have gotten if we had a thermometer on our own property.

In the next week or so, we’ll be sampling buds and canes to see how well we survived the big chill. This is a first for us, and I have no idea how we did. But I can say this: I feel a whole lot better because of the work we did. Even if we lose the vineyard – which I think is a low probability outcome – I’ll feel better knowing that we did everything we could. If we had done nothing at all and lost only half the vineyard, I would feel much worse.

Wine grape growing is agriculture and like farmers everywhere, we live at the mercy of whatever Mother Nature throws at us. As Chris Hill, one of Virginia’s vineyard pioneers, told me during one of our classes – and this is a major paraphrase – the averages (temperature, etc.) are important, but it’s the records that kill you. And this year was one for the books.

February 27, 2015 | By | 8 Replies More
%d bloggers like this: