Freeze Warning

Vicissitudes. That's the word that popped into my head this morning. It's a pretty great word, but comes to mind for a not-so-great reason: Our vineyards in The Brogue and Stewartstown are under a freeze warning for tonight, and possibly for Thursday night as well. Vicissitudes can be positive or negative things befalling us by chance. There's usually nothing we can do about them. In the case of viticulture, this is certainly true. Ish.

Growing grapes in a temperate climate (as opposed to in more predictable warmer climates such as Australia or Napa) means that we have to do more vineyard management to deal with things like rainfall and cold. The cold can threaten our vines during the dead of winter, when below-zero temperatures can literally kill the vines, and during two other vulnerable times: in late harvest time, when the grapes are hanging ripely on the vines, and in early- to mid-spring. Here in April and early May, our grapevines experience bud-break (also thrillingly called bud-burst). It's an exciting time of the year, when the leaves push up and out through the vines, one variety at a time, turning the vineyard a wonderfully hopeful shade of spring green. It's also the time of no return.

Merlot in the upper Cadenza Vineyard

Once the sap is running and bud-break has occurred, below-freezing temperatures (anything below 32°) can cause real damage. If the new buds are killed by cold, our only hope is that the vine will develop secondary growth, later and significantly less fruitful than the growth we'd like to see in as long of a growing season as possible.

From recent devastating news, we've heard that late spring frosts have absolutely decimated French vineyards in the past weeks. Vineyards in all of the growing regions of France have sustained significant damage, as noted in sympathetic articles from all around the world. Vineyards with a lot of money can implement frost mitigation strategies, including helicopters, windmills, and smudge pots designed to move warm air into vineyards and cool air out. Sprinklers can also be used; if buds are continually coated with water, the water will freeze and keep the interior at the magical 32°. Many places (such as ours) cannot afford these kinds of technologies. French growers are anticipating the partial or complete loss of grapes from the 2021 vintage. For many already this year, it's over before it's even gotten started.

At this point in our growing season in The Brogue, we've experienced bud-break at some places in our Merlot and Chardonnay blocks, as well as in a few Petit Verdot and Cabernet Franc vines. Other varieties such as Cabernet Sauvignon, which develop a bit later in the season, are not as vulnerable right now. It's the early-bloomers who are the canaries in our coal mine, so to speak.

Not in all of the growing years here from the vineyard's first planting in 1973 through 2009 was there any kind of spring frost damage. Climate change, however, has meant that in the past dozen years, we've been under potentially dangerous freeze warnings several times. The most damage we've ever sustained was actually last year, when cold nights in early May caused the loss of a significant (25%) number of Chambourcin grapevine buds at our Stewartstown vineyard and less significant (about 10%) number from our upper Chardonnay and Cabernet here in The Brogue.

There is one trick Carl has up his sleeve, when it comes to spring frost mitigation. It's called KDL. KDL is a potassium fertilizer designed to be sprayed on grapevine buds to lower their freezing point and increase freeze resistance. When we get a warning such as the one for tonight, he can apply KDL on susceptible grapevines with the hopes of getting another degree or two of cold protection.

In farming, of course, there's a lot that we can't control. (Those darn vicissitudes and all.) I've sometimes noted that our lack of control over things like climate and climate change can make me feel humble. We can also feel helpless, frustrated, as humans do when feeling powerless. It feels better to be able to predict and to act. We stand vigilant. We hope. And, yeah...I even cross my fingers sometimes. Carl straps on his backpack sprayer.

Chardonnay sap flowing

Days and nights like these do connect us to all of those in our region--and over there in France, and all over the world, for that matter--whose livelihood also depends on growing conditions and the weather. Isolated as we may be on this plot of land as the climate changes and temperatures get more wild, at least we're all still in it together.

End-of-April Update: After about a week of warmer weather and vineyard growth, Carl was able to assess that we did in  fact lose about 20% of the buds in our early-breaking varieties (lower Chardonnay, upper Merlot in our vineyards in The Brogue) and lesser damage in a few other places. This will affect our yields this year, but not as significantly as last vintage.