Part One: 14 degrees Fahrenheit
Vates kale overwintered in our garden. I’ve long been interested in how cold-tolerant various vegetables are. We had two nights at 14 degrees Fahrenheit (-10C) and several others in the teens in December. What survived? We have Tyee spinach under rowcover, and Vates kale. The senposai was still alive, but some of the midribs had brown streaks. Sadly we don’t have any leeks this winter, as we lacked enough workers to tend them in late summer. We had a nice bed of Deadon cabbage, and some small heads of Melissa savoy that missed the bulk harvest were also alive. The Gunma cabbage stumps had some leaves and tiny heads still alive, but the Tendersweet were history.
Our chard had all the leaves cut off in November, and seemed to be dead. Some winters it hangs on later, if we leave some foliage to help it regenerate.
The oats cover crop we sowed in August and early September were pretty much dead. All the broccoli looked dead. That’s as expected for the temperatures. Often we don’t get nights this cold till January – the cold came early this winter.
Our hardneck garlic tops looked to be in good shape. The Polish White softneck tops are considerably smaller and look like they suffered. They will grow back if they have died. Some of our Chandler strawberry plants look dead. Either that or they are extremely dormant! The deer were killing them off by eating the leaves. Too many deer!
The hoophouse was still bursting with great food. Plenty of salad greens: lettuce; various kinds of mizuna and ferny mustards like Ruby Streaks and Golden Frills and Bulls Blood beet leaves. And for salads or cooking we have spinach, chard, tatsoi, radishes, scallions, baby Hakurei turnips and their tasty greens, Red and White Russion kales, and more senposai. In January we start on the heading Asian greens: pak choy, Chinese cabbage, Tokyo bekana and Yukina Savoy. The first sowing of tatsoi (9/7) was starting to bolt, so we cleared that. The first round of baby lettuce mix (10/24) was ready for its second cut. I love working in the hoophouse on sunny winter days.
Part Two: Two Nights at 4 Degrees Fahrenheit
We had the Polar Vortex, which in our part of central Virginia, meant two nights at 4 degrees, Monday 1/6 and Tuesday 1/7 nights. How did it go?
Before the Prelude to the Big Chill, when we got 9F, I harvested the odds and ends of small cabbages left in our main patch. Quite worthwhile, I got two 5-gallon buckets. Between the 9F and the 4F nights, I decided to gather the Deadon cabbage, which we grew with January harvests in mind. There was some freeze damage, so in future I’ll say that Deadon is good down to 10F, but not lower. I got two full net bags and two more buckets of small ones. I left one smaller and one larger cabbage as sacrificial victims in the cause of better information for next year. When we got 4F, the smaller one died and the larger survived.
Senposai outdoors in November. One of the other gardeners harvested the last of the outdoor senposai. Another couple of buckets of tasty food.
I took another walk round the frozen garden after the Polar Vortex, to see what was still alive. The Tyee spinach under rowcover, and the Vates and Beedy’s Camden kale without rowcover were all still alive! There was some freeze damage in spots on the spinach leaves, but plenty of good meals still to come!
Our hardneck garlic tops suffered some damage but didn’t get killed back to the mulch level. The Polish White softneck tops are considerably smaller and they too were still alive.
We had the remains of a lettuce nursery bed, still holding surplus transplants from September sowings that we didn’t need for our greenhouse or hoophouse. A good chance to see which ones are hardiest! Here’s the scoop: Still alive in the centers – Winter Marvel, North Pole, Tango, Green Forest. No longer alive – Salad Bowl, Red Salad Bowl, Winter Wonder, Red Tinged Winter, Merlot, Red Sails, Outredgeous, Roman Emperor, Revolution.
At nearby Acorn Community, the home of Southern Exposure Seed Exchange, they had some young but mature heads of cabbage outdoors. The Late Flat Dutch, Early Flat Dutch and Chieftain Savoy all survived one night at 6F. (It’s usually two degrees warmer there than at Twin Oaks on winter nights).
Meanwhile I’m tracking the Blue Ridge kale grown by Clif Slade in his 43560 Project at Randolph Farm, VSU. The Blue Ridge survived. It got down to 9F there. Not as cold as Louisa County! Blue Ridge is taller than the Vates we grow, and I’d like to try it here, if it can survive our winters. Otherwise not!
Our winter hoophouse with Yukina Savoy and Pak Cho. In the hoophouse, we covered all the beds with thick rowcover on Monday afternoon, and didn’t roll it up till Thursday, after the warmer weather returned. There was a tiny bit of freeze injury on some turnip greens that poked out the side of the rowcover, and some on some stems of Tokyo Bekana. I think the rowcover saved the crops! Also, a bad thing happened. it was very windy Monday night and the west window blew open. Argh! Of all the nights to have an open window. Memo: fix the latch to make it stronger.
I didn’t enjoy the really cold weather. I was anxious about the crops and the plumbing! But I can see two silver linings: I now have more information about cold-hardiness of various crops, and hopefully some pests will have died. Now we’re getting ready for another two cold nights, tomorrow and Wednesday.
Part Three : Two Nights Below 0 degrees Fahrenheit
It got even colder.We got the big-round 0 degrees 1/22-1/23, then a few nights at 5 degrees or 6 degrees, and then the big insult: -4 degrees on the night of 1/29-30. What’s still standing?
The Tyee spinach under thick rowcover has sustained big damage, showing as patches of beige dead cells. It will recover. Meanwhile we can eat from the more-protected spinach in the coldframes and the hoophouse.
The Vates kale without rowcover is still alive, but badly damaged. The big leaves are crunchy and brown round the edges, and some of the inner leaves are dead. I hope it will grow back, but we won’t be able to pick that for a while. The Beedy’s Camden kale looks worse – the big leaves have died and flopped over. Not sure if it will recover.
Our hardneck garlic and Polish White softneck tops are killed back to about one inch up from the mulch. Equally hardy, it seems.
In the lettuce nursery bed, still holding surplus transplants from September sowings that we didn’t need for our greenhouse or hoophouse, only the Winter Marvel shows any signs of life. So that variety gets the prize for cold-tolerance here!
In the hoophouse, we covered all the beds with thick rowcover every night it looked like dropping below 10F inside. Almost everything survived – we only got some minor stem freezing on some turnips and Asian greens. We have been eating Pak Choy, Tokyo Bekana, Yukina Savoy, various turnips and their greens (Hakurei, White Egg, Oasis, Red Round), also plenty of lettuce leaves, radishes, scallions, and some spinach. We have small amounts of mizuna, Ruby Streaks, Bright Lights chard, Bulls Blood beets to add to salad mixes, and Red Russian and White Russian kale growing slowly.
We are not the only people tracking the effects of the unusually cold weather. The February Growing for Market magazine opens with an article by Ben Hartman “Testing the Limits of Cold Tolerance”. He farms in Goshen, Indiana, using two double-layer plastic greenhouses heated to 30F (yes. I said heated!) and two unheated.
Read more from Pam Dawling on her blog.