My Garden Survived the Polar Vortex!

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polar vortex garden

This post might aptly be titled, “Be Careful What You Wish For…”

While chatting with my mother-in-law a few weeks ago, I expressed my hopes for a colder-than-average winter. Sounds crazy, I know, but hear me out.

Since my blog launched last year, I’ve tried to take the “grow your own” and “local food” movements a step further —  I want it to become a practice that is done the entire year, not just May through October. I’ve been preaching the virtues of winter gardening with low tunnels, not just on this blog, but also around eastern Kentucky mountain communities through my guest lectures for Grow Appalachia and the Cooperative Extension Service. Many people are buying into the message and have successfully grown through fall and winter for the first time. Some are so convinced that they’ve sworn off growing broccoli in the spring (since they’ve witnessed the decreased pests, higher yields, and better taste of fall broccoli), and are already planning expansions of their gardens in Fall 2014.

That’s exciting stuff, folks! I’ve helped people accomplish something they never thought they could do — feed their families fresh, healthy food from their gardens through at least the Thanksgiving or Christmas holidays (many of them longer). No heat, no fancy greenhouses, no expensive inputs required. How rewarding is that?!

That said, there have also been a few naysayers. You see, lately our winters haven’t been typical here in plant hardiness zone 6b. Whereas a few decades ago, our temperatures routinely dipped to sub-zero (F) levels at least once every couple of years, we’ve not seen those extremes since 1994 (which happened to be a record-smashing year in many states). So it seems too risky to some folks to grow a winter garden — what would happen if those sub-zero temperatures returned?

Well, return they did…

What has come to be known as the “Polar Vortex” arrived at our home on Monday, January 6th, after an unseasonable, spring-like Sunday with a high temperature near 52 F (11 C). When it was all said and done, we reached a record low of -8 F (-22 C) by early Tuesday morning. The real kicker was the windchill, however, which was a frigid -36 F (-38 C). Since Wednesday morning, temperatures have steadily been moving upwards, and some of the tunnels finally thawed enough today for me to remove the covers and give a report.

I can now tell the naysayers exactly what happens in sub-zero temps  — your garden CAN survive!

I'll be honest: Seeing this under the low tunnel covers had me bopping around the garden, singing Gloria Gaynor's "I Will Survive."

I’ll be honest: Seeing this under the low tunnel covers had me bopping around the garden, singing Gloria Gaynor’s “I Will Survive.”

 

If you’re a regular reader of my blog or Facebook page, you know that this year I’ve planted about 60 varieties of cold-tolerant vegetables in the winter garden, under various degrees of low tunnel protection (or exposed), in a quest to find out which plant and cover combinations are ideal for winter growing.  My low tunnels have been covered with varying weights of fabric (Agribon-19 or Agribon-30), clear plastic sheeting, and various combinations thereof. Although many of the results I’m sharing with you now are preliminary, I’m so excited by what I’ve seen so far that I just can’t resist sharing a few of them.

 

The most widespread plant losses were in the low tunnel covered with only Agribon-19, which typically provides frost protection down to 28 F (-2 C). To this point in winter, despite temperatures in the mid-teens that would normally kill exposed lettuce, there had been no losses in this tunnel (with the exception of freeze-damage to some Japanese Giant Red Mustard). Due to the extreme sub-zero temps brought by the Polar Vortex, there were wide losses of lettuce and Asian greens. What came out unscathed? Mache, four types of kale (Vates, Red Russian, Lacinato, and Rainbow Lacinato — the latter with some freeze damage), and claytonia.

No signs of burn or wilting in this mache

No signs of freeze-burn or wilting in this mache

-8 F proved too cold for the lettuces under Agribon-19

-8 F proved too cold for the lettuces under Agribon-19 (kind of expected, right?)

These Asian greens have turned to mush under Agribon-19.

These Asian greens have turned to mush under Agribon-19, but if the roots and crown survived, they may shoot new growth. Time will tell.

 

Conditions were  improved in the tunnels protected with Agribon-30, which provides slightly more protection (to 26 F). All kale varieties looked fantastic, but there was varying degrees of freeze damage on the Asian greens (mizuna appears to be the least cold-tolerant of the group, followed by tatsoi and pak choy varieties — various Asian curly mustards faired much better).

Beets varied in cold-tolerance, as shown with Detroit Dark Red (foreground) against the upright Mammoth Red Mangel behind it.

Beets varied in cold-tolerance, as shown with Detroit Dark Red (foreground) against the upright Mammoth Red Mangel behind it.

 

Arugula stands erect against a backdrop of Red Russian Kale

Arugula stands erect against a backdrop of Red Russian Kale

 

My two beds of lettuce are normally covered with a single-layer of Agribon-30, but the evening before the Polar Vortex arrived, I added an additional layer on one bed, and another two layers on the other for insurance. To my surprise, almost all of the lettuce appears to have survived, although a few varieties appeared to be more susceptible.

I harvested a fair amount from each lettuce plant before the big freeze, but was pleasantly surprised to find them intact today.

I harvested a fair amount from each lettuce plant before the big freeze, but was pleasantly surprised to find them intact today.

 

The tunnels which faired the weather best were the two beds protected under clear plastic, including one which also has an inner layer of Agribon-19. Temperatures in this latter tunnel stayed the warmest of all, reaching a low of 10 F during the Vortex’s lowest temperature (-8 F), but warming to 34 F when the sun was shining and the ambient temperature was 10 F. Almost all plants in this most-protected tunnel appear to have survived, including various Asian greens, root crops, kales, chards, spinach, kohlrabi, parsley, chervil, endive, radicchio and lettuces, although the beets and a variety of rutabaga (Nadmorska) have droopy tops.

Asian greens protected with a single layer of clear plastic sheeting.

Asian greens protected with a single layer of clear plastic sheeting.

 

A close-up of the Asian greens bed under a single layer of clear plastic. Mizuna (top right) and Japanese Giant Red Mustard (bottom left) were the most cold-susceptible.

A close-up of the Asian greens bed under a single layer of clear plastic. Mizuna (top right) and Japanese Giant Red Mustard (bottom left) were the most cold-susceptible.

Various chards and kales... still looking gorgeous for the most part!

Various chards and kales… still looking gorgeous for the most part!

What a difference the type of cover makes! Purple mizuna under plastic + Agribon (left), vs under Agribon-30 only (right)

What a difference the type of cover makes! Purple mizuna under plastic + Agribon (left), vs under Agribon-30 only (right)

 

I’ll provide more updates on plant survival and harvest quality in future posts, after sufficient time has passed to see if any latent damage will appear, or if regrowth occurs in plants thought to be lost. Over all, I couldn’t be happier with the outcome, and celebrated this evening by roasting some freshly-harvested turnips, rutabaga, and carrots from the garden.

I’d love to hear how you survived the Polar Vortex. How did your garden fare?

 

Want to learn more about vegetable gardening in winter? Check out the “Winter Growing” tab at the top of the page for links, including how to construct your own low tunnels, which vegetable varieties are appropriate for cold weather, and more! And don’t neglect learning what you can from the master: Maine farmer, Eliot Coleman. His fantastic books, like “Four Season Harvest,” have provided a wonderful head start for me and other winter gardeners. I also highly recommend Niki Jabbour’s most recent book, “The Year Round Vegetable Gardener,” as a great resource for gardening in all seasons.

 

10 Comments

  1. Andrea

    January 10, 2014 at 8:39 am

    Living in Central Texas it only got the lowest of about 19 degrees F. Makes me realize that if you can do it up there that I can grow things down here. I will start working on my plan for next winter. Thanks!

  2. Pingback: Surviving the Polar Vortex | Bluestone Garden Blog

  3. Kelly

    January 13, 2014 at 10:35 am

    I’ve not tried winter gardening here in Northern Illinois, but have wanted to. Your blog makes me think it would truly be possible. My biggest concern besides the freezing temps, is the wind. I wonder how you keep your tunnel covers from blowing off/away? Also, what are the hoops made of, and how do you keep them anchored in the ground? We have terrible soil, so all my growing is done in raised beds. Do you suppose a raised bed would fair as well for winter gardening? Thanks1

  4. cbellbooth

    January 19, 2014 at 7:06 pm

    Living in Dayton, Ohio, and wondering if my new asparagus plants have survived the polar vortex. Time will tell…

  5. Sally Oh

    June 23, 2014 at 4:19 pm

    Where did you get your Agribon 19? Lowe’s and Tractor Supply don’t carry it… thanks!

    • Ma Hubbard

      June 24, 2014 at 8:07 pm

      Great question! In my part of the world, I have to either order Agribon (usually from Johnny’s Selected Seeds, American Nettings and Fabric, or Four Season Tools), or drive several hours to a farm supplies store. You’ll also find it sold as fabric row cover, Remay, or floating frost blankets — Agribon-19 corresponds to the “light-weight” version of these fabrics. I’m hoping that one day, row cover will be so ubiquitous for winter gardening that every big box home supply store will carry it!

      • Sally Oh

        June 24, 2014 at 10:12 pm

        Thank you, that explains everything 🙂 On a positive note, there is no shade cloth anywhere either. I’m thinking that means more gardening going on!

  6. Pingback: How to Plant Your Fall/Winter Garden

  7. Veletta

    November 14, 2014 at 9:15 pm

    It will be in the 32 tonight here in Long Island, NY. I have my collards, carrots and kale covered with Agribon 19, Winter Density Lettuce under Agribon 30. They are under high hoops so should I just cover crops with Agribon30 within the hoops?

    • Cathy

      November 15, 2014 at 10:54 pm

      Everything you’ve planted should easily survive a 32F night. In my garden, I don’t cover them until temperature forecasts drop to 25F (with exception of covering mature lettuce around 28 F, because it is a little more sensitive) — they sweeten up nicely after getting kissed by frost.