Here’s an end-of-year pictorial post with photos from our hoophouse through the year. Few words! Enjoy your holidays. Maybe Santa will bring you a hoophouse?
‘Tis the season – after the relaxation of the holidays – time for garden planning. Inventory your seeds left from last year, peruse the catalogs and prepare your seed orders. The earlier you get them in, the more likely you are to get the varieties you want, before anything is sold out.
I notice that readers of my blog have been looking up the Twin Oaks Garden Calendar, also known as The Complete Twin Oaks Garden Task List Month-by-Month. You can search the category Garden Task List for the Month, or you can click on the linked name of the month you want. At the end you can click on “Bookmark the Permalink” if you might want to refer to this in future. Remember, we’re in central Virginia, winter-hardiness zone 7a. Adjust for your own climate.
Meanwhile, despite the turn to cold weather, we are not huddled indoors all the time. Each day, one or two of us sally forth to harvest enough vegetables to feed the hundred people here at Twin Oaks Community. Outdoors, in the raised bed area, we have winter leeks, Vates kale, spinach and senposai. We could have had collards but we lost the seeds during the sowing period, so we have lots of senposai instead. Senposai leaves (the core of the plant may survive 10F), are hardy down to about 12F. I noticed some got a bit droopy when we had a night at 15F. Collards are hardier – Morris Heading (the variety we grow) can survive at least one night at 10F.
In the hoophouse, we have many crops to choose from: lettuce, radishes, spinach, tatsoi, Yukina Savoy, Tokyo Bekana, turnips and turnip greens, scallions, mizuna, chard, Bull’s Blood beet greens.
Pak Choy and Chinese cabbage heads are filling out, ready for harvest in January.
Tokyo Bekana, a non-heading Asian green, has large tender leaves, which we are adding to salad mixes. It can be used as a cooking green, but only needs very light cooking. It will bolt soon, so we are harvesting that vigorously, not trying to save it for later.
The kale and senposai in the hoophouse are being saved for when their outdoor counterparts are inaccessible due to bad weather. The spinach is added to salad mixes, or harvested for cooking when outdoors is too unpleasant, or growth slows down too much.
Another kind of planning I’m doing right now is scheduling my speaking events for the coming year and practicing my presentations. Last week I updated my Events page, and this week I’m adding a new event: The September 21-22 Heritage Harvest Festival.
I might pick up a couple of events in late April and early June, but that’s just speculation at this point.
Right now I need to practice for the CASA Future Harvest Conference January 11-13. Cold-hardy Winter Vegetables and a 10-minute “Lightning Session” on using graphs to plan succession plantings for continuous harvest. Click the link or my Events page for more on this.
In June I told you about Tokyo Bekana, a light green tender-leaved, white-stemmed green which can be cooked, or used as a substitute for lettuce in hot weather. Because summer in Virginia is a hard time for leafy greens, July’s Asian green is very similar – Maruba Santoh. Maruba Santoh has smoother, wavy, less ruffled leaves than Tokyo Bekana.
To show you I’m not being a slouch, I’ll include some pointers on sowing Asian greens for fall, because now is the time – in our climate at least. Here’s what one of my favorite seed suppliers, Fedco Seeds has to say:
Maruba Santoh (35 days) Brassica rapa (pekinensis group) Open pollinated. With Maruba you get four vegetables in one. The loose round vibrant chartreuse leaves provide a mild piquant mustardy flavor while the flat white stems impart a juicy crisp pac choy taste. High-end chefs like to use the blossoms. Market grower Scott Howell finds the flavor more subtle and complex than that of other greens and cuts Maruba small for his mesclun. Fairly bolt tolerant, so plant after the early spring flea beetle invasion subsides.
Fedco is in Maine and we’re in Virginia, so things are a little different. The information on their website about pests and diseases is good. Our worst brassica pests are harlequin bugs.
We grow our summer brassica seedlings and transplanted Asian greens under ProtekNet on hoops. On the Dubois link, study the Dimensions and Specifications tab, then download the brochure from that tab. Study the Descriptions tab – it tells you which insects are excluded by each size mesh. Be sure that you choose the right size mesh for the bugs you want to exclude. Flea beetles and thrips are small – you need a small mesh. Johnny’s is now marketing the close-mesh ProtekNet as “Biothrips” insect netting, and they also have a comparison chart of rowcover and insect netting on their site.
Kitazawa Seeds also sells Maruba Santoh seed, under the Chinese Cabbage heading. Like most brassicas, Maruba Santoh does best in cool weather, although it is somewhat heat tolerant (or “warm tolerant” as we call it in Virginia.) It tolerates heat better than Napa Chinese cabbage does. To avoid bolting, keep the plants above 50F (10C) at all times, but particularly avoid prolonged spells below this “bolting trigger” temperature.
Maruba Santoh will germinate at temperatures between 50-85F. Seedlings emerge in just 3 days in summer. For summer use, direct sow, thin the rows for baby salad mix, then let the “heads” (it doesn’t actually head up) develop to full size (6-10″ tall) after about 35-40 days. Or transplant two week old starts. We tend to grow our plants quite big (12″ tall) and harvest by the leaf, several times over. Maruba Santoh makes a fine substitute for lettuce, and a tasty quick-cooking green.
To calculate sowing dates, work back 40 days from when you want to harvest, and sow more every week or two until you run into the fall slowdown temperatures, or you go back to eating lettuce in salads and cooking chard and kale. If you still have Maruba Santoh growing in the fall, know that it will be frost tolerant to 25°F (-4°C). No hurry.
Maruba Santoh can also be grown at other times of year: spring and fall outdoors, winter in the hoophouse. The seedlings have large cotyledons and make good microgreens too.
Kitazawa’s Culinary Tips include: Use in salad, sukiyaki, ohitashi, yosenabe, stir-fry, soup and pickling. Kim chi here we come! (If we had surplus.)
Next month I will talk more about Asian greens outdoors in fall. Now is the time to sow for fall harvests. We start in late June, and sow more in early July. We always make two sowings a week apart, for insurance. We are aiming for greens to feed us in early fall, before the kale is ready, and into the winter, harvesting by the leaf. But Asian greens can be sown all the way up to two months before your first fall frost date. For us, that means August 14-20. If you want to make sowings now, consider senposai, komatsuna, pak choy, tat soi, Yukina Savoy, and Chinese cabbage.
I have two posts on the Mother Earth News Organic Gardening Blog that I haven’t told you about yet. So if it’s too hot out, or it’s raining (don’t make me envious) seek shade and read more. The newer post is Insectaries: Grow Flowers to Attract Beneficial Insects, and the previous one is Planting Leeks.
Last week when writing about Lettuce Varieties for January I mentioned how we grow all our outdoor lettuce as bare root transplants. From January through to the end of April, we sow lettuce seed in open flats. After that date, we sow in outdoor nursery seed beds, and simply dig up the transplants when big enough and replant them in our raised beds. We transplant 120 lettuce outdoors each week until early October and then transplant in our greenhouse and our hoophouse. We also grow many other crops (all the easy to transplant ones) in open flats, or in nursery seed beds.
This method has gone “out of fashion”, but perhaps it will come back in! Atina Diffley (Author of Turn Here Sweet Corn and Wholesale Success) has written a blog post about bare-root brassica transplants at atinadiffley.com/blog/. She has written a thorough-and-concise 9 page manual Seed Beds: Bare Root Field-grown Brassica Transplant Production. It includes a chart of pros and cons of bare-root transplants compared to container-grown greenhouse transplants.
Using bare-root transplants does require a bit more attention to technique than popping plugs into the ground. But it’s not that difficult and we train new people every year with success.
Why bare-root transplants?
Bare-root transplants save a lot of time and money, compared to growing in flats. They also save on valuable greenhouse space. The plants get very sturdy, because they have the full depth of soil in which to develop big roots. Starts grown in outdoor seedbeds are already acclimated to cooler conditions than plants in your greenhouse. They are less prone to drying out than seedlings in flats, but do be ready to protect them from bugs.
Which crops work best?
Bare-root transplants can suffer more transplant shock than plugs, so start with “easy to transplant” crops, such as brassicas (cabbage, kale, collards, broccoli, Brussels sprouts, kohlrabi), lettuce, onions and leeks. Tomatoes and peppers are worth trying next. See the Chart “Relative Ease of Transplanting Bare-Root Vegetable Seedlings” free online in Knott’s Handbook for Vegetable Growers. Avoid trying bare-root cucurbits (squash, melons, cucumbers).
Bare-root transplants can be used on any scale, from backyard to large farm. See the impressive photos of huge beds of cabbage transplants in Atina Diffley’s manual. They can be used at various times of year, and from indoors to outdoors and vice-versa.
Spring bare-root transplants started in a hoophouse, planted outdoors.
For the earliest spring transplants, bare-root hoophouse starts are a nice option. For us, onion seedlings overwintered in the hoophouse have worked very well. Seedlings outdoors or in a cold-frame suffer too much winter-kill. We don’t want to fuss with flats in November-February. We’re in zone 7, at 38̊ N. We sow onions in the soil in the hoophouse November 10 and 20, with a backup sowing on December 5. We plant them outdoors as early in March as we can. The onions get to thin-pencil-size by March 1, which we couldn’t do from a spring sowing. Onion roots are tough and thick, not thread-like – they are easy as bare-root transplants.
We sow spinach, collards and kale in the hoophouse in mid-late January and plant them outdoors in early March. This is a lot less work than using flats, and our comparison trials with bare-root spinach showed results were just as good as spinach in Speedling plug flats. We have tried early lettuce transplanted from the hoophouse, but the plants were not as sturdy as those in flats.
Outdoor bare-root transplants
See my book Sustainable Market Farming, for more details of growing outdoor bare root transplants. We grow lettuce this way from April to September, and fall brassicas in June and July, in one of our permanent raised beds where the soil is friable and free-draining. Also see Atina Diffley’s manual for cultivation tips.
We grow outdoor cabbage, broccoli, collard, senposai and Yukina Savoy transplants in seedbeds for 3-4 weeks in June and July, covered with ProtekNet on hoops. We transplant in July and early August for harvest in October and November. We prefer this to direct sowing, because it is much easier to keep the relatively small seedbed watered and bug-free. For large amounts use an EarthWay seeder. Atina Diffley recommends the leek seed plate for brassicas.
Outdoors to indoors
In September we make an outdoor seedbed for crops to transplant into our hoophouse in October. The late summer hoophouse crops get a few extra weeks to finish up. Because the hoophouse can be warmer than ideal for lettuce germination until well into fall, it often works better to start plants in a cooler location, then move the plants. In September in our climate, four-week old lettuce plants will be a good size.
As well as ten varieties of lettuce, we sow various Asian greens and Brite Lites chard. Nine days later we sow another ten varieties of lettuce, white and red Russian kales, senposai and frilly mustards such as Ruby Streaks, Red Rain, Golden Frills, Scarlet Frills as well as green mizuna. We cover the seedbeds with hoops and ProtekNet and water daily. Transplanting these plants starts October 1 with the fast-growing pak choy, Chinese cabbage and Tokyo Bekana. The other transplants follow, as they reach the right size.
Stay indoors in winter
In October in the hoophouse we sow short rows of “brassica fillers”, mostly senposai, Tokyo Bekana and Maruba Santoh. These grow fastest, which becomes more important in the dark winter days. We fill gaps in any brassica bed, that occur either because of disease, or of harvesting. In late October and early November we sow filler leaf lettuce varieties and filler spinach. These extra plants help us out if something goes wrong, and give us the chance to grow some extra crops after the first ones have been harvested.
How much to sow
Our formula for sowing seedbeds in the hoophouse is to divide the final row length of brassica plants by 10 to give the minimum length of seed row to sow. These plants will be transplanted 10″-12″ (25-30 cm) apart. For onions (to be transplanted 4″ (10 cm) apart), we divide the number of plants wanted by 20 to give the row feet (67/m), but we sow this amount twice, about 10 days apart. Outdoors for the fall brassicas, we sow around a foot (30 cm) of seed row for every 12′-15′ (3.6-4.6 m) of crop row, aiming for 3-4 seeds per inch (0.75 cm apart). These plants will be transplanted 18″ (46 cm) apart. It’s important to weed and thin the seedlings to 1″ (2.5 cm) apart soon after they emerge.
Transplant age and size
There is quite a lot of flexibility about when a start can be transplanted, but there are accepted ideals to be aimed for. The University of Florida Vegetable Horticulture Program Vegetable Transplant Production page has a wealth of transplant information. Transplants grown over winter or in very early spring in a hoophouse will take longer to reach plantable size than those sown in spring or summer.
Suitable conditions for transplanting
The ideal conditions for outdoor transplanting are mild windless afternoons and evenings just before light steady rain. Transplanting late in the day gives the plant the chance to recover during the cooler night hours when transpiration is slower. Shadecloth or rowcover can reduce the drying effects of wind and sun. Damp soil is important before, during and after transplanting.
Bare-root transplanting technique
When you dig up your bare-root transplants, leave some soil clinging to the roots, to help the plants re-establish quicker. They don’t need a full handful of soil for each plant. Just dig up a clump and give it a light shake, to leave the majority of the soil behind, and some still on the roots. This means less damage to the root hairs. Be sure to dig deep enough so you don’t damage the tap roots. Water your plants the day before and an hour before lifting (pulling) them. In hot weather, keep the plants as shaded as possible while transplanting.If necessary water the soil ahead of planting.
We use plastic dish-pans to carry our plants from seedbed to field, and I tell people to only dig up what they think they can transplant in half an hour, so that plants don’t sit around for too long. Push the trowel into the soil, using the dominant hand, push it forwards, shake a plant loose from the clumps in the dish-pan with the other hand, and slip a plant in behind the trowel. Pull out the trowel, keeping it in your hand while you close the soil against the stem with your planting hand and the trowel. (Efficient workers keep a hand on the trowel at all times, never setting it down.) Move to the next spot and repeat. When setting out a large number of plants, water every 20-30 minutes if you don’t have drip irrigation running (a bit less often if you do) regardless of the number of plants set out. If the person is skilled and moving fast, and the weather is not outrageously hot or windy, I might let an hour go by before pausing to water. The advantage of getting a lot of plants in the ground proficiently and quickly might outweigh the need to water more often, as the plants are not having their roots exposed to the air for as long when they are planted fast. The hand-watering really helps the soil settle around the roots, and after that the damp soil can wick moisture from the irrigation towards the plant.
Aftercare: water, rowcover, shadecloth
Water your plants the day after transplanting, on days 3, 7 and 10, and then weekly, if it doesn’t rain when you’d like it to. Shadecloth draped over recently transplanted crops can help them recover sooner from the shock in hot sunny weather. We use 50% shade, in 6′ (1.8 m) width, with wire hoops to hold the shadecloth above the plants. This improves the airflow as well as reducing the abrasion or pressure damage done to the plants. The airflow through shadecloth is better than with floating rowcovers. ProtekNet allows good airflow too, and keeps bugs off.
Here we are in the shortest days. What are we harvesting from our hoophouse (high tunnel)? Many different crops, mostly leafy greens, but with the addition of radishes, turnips and scallions. I’ll start with those.
We’re harvesting our third sowing of radishes, sown on 10/30. We like the vari-colored Easter Egg radishes and the long White Icicle for this time of year. Cherry Belle also works in this sowing, but not later. Like Sparkler, it gets too fibrous in winter.
Our favorite scallions are Evergreen Hardy White, which are extremely cold tolerant. They are also slow to grow. We are starting to harvest the ones we sowed 9/6. The second sowing (which followed the first radishes on 11/18) are just spindly little blades so far.
The turnips (and their greens) which we are starting to harvest at tangerine-size, are Hakurei and Red Round, from a 10/14 sowing. We made a second sowing of turnips on 10/26, but we over-watered them and got patchy germination. We filled the gap with a late sowing of brassica salad mix. This is a mixture of random leftover brassica seeds (varieties we didn’t like, seed that is getting a bit old) which we sow and then cut with scissors about an inch above the soil once they get to about 4″ tall.
Just like baby lettuce mix. We are on our second cut of our 10/24 lettuce mix. We buy the mix already made, although if we get close to running out of seed, we have been known to mix in some seed of basic varieties like the Salad Bowls, that do well in the winter high tunnel. We also have lots of big lettuce plants. We take leaves off those for our salad mixes when we don’t have baby lettuce mix at the right stage for cutting.
Into the salad mix we add chopped mizuna and its spicier cousins Golden Frills, Ruby Streaks and Scarlet Frills. These add loft, visual interest and flavor. For color we also add chopped Bulls Blood beet leaves and chopped small leaves of Brite Lites chard. As well as mixing the colors and shapes, I try to have at least one representative of each of three crop families: spinach, chard and beets; lettuce; brassicas such as mizuna, baby kale leaves, small leaves of Tokyo bekana, Yukina savoy, tatsoi.
For cooking greens we are harvesting leaves of Russian kale (transplanted 10/22), our first chard (transplanted 10/16), spinach (sown 9/6 and 10/24), senposai (transplanted 10/24), Tokyo bekana (transplanted 10/9) and Yukina savoy (transplanted 10/24). it takes 10 gallons of greens to provide 100 people with a healthy serving each. We aim to provide the cooks each day with a choice of two or three different cooking greens.
We are also harvesting some greens as whole heads now. We are clearing our first planting of tatsoi (sown 9/7), which has been getting ready to bolt for a couple of weeks now. Likewise the Tokyo bekana, which starts to bolt at the end of December.
We are also cutting big heads of Chinese cabbage and Pak Choy. As we harvest these, we fill the gaps at the end of the day with replacement plants. My current favorite is senposai, as it is very quick to grow and can be eaten at any stage. (And of course, it’s very tasty, otherwise I wouldn’t even mention it!) We reckon 12/31 is the last worthwhile date for us to do this gap filling with Asian greens. After that we use spinach or lettuce transplants up till 1/25, then only spinach (up till the end of February). We’ve found that planting after those dates doesn’t produce harvest, just wasted time!
The Yukina savoy doesn’t really start bolting until the last week of January normally, but with the freakish warm weather we’ve had this December, we might get early bolting. I don’t know if this crop bolts mostly in response to day length or to temperature. I guess we’ll find out.
We’ve ordered our seeds, we’re planning our next hoophouse crops and our schedule for sowing seedlings in the greenhouse. And this is the slow season!
I had a good time at the Heritage Harvest Festival this past weekend. My Friday workshop on Crop Rotations for Vegetables and Cover Crops in the Woodland Pavilion had about 56 participants. If you missed it or want to see it again it’s here. Most of my slide shows are on SlideShare.net. Search for Pam Dawling and click on the one you want to see.
On Saturday I did my presentation on Asian Greens. And this morning I sowed Blues Chinese cabbage, Yukina savoy, Tokyo Bekana, and pak choy, as well as Brite Lites Chard and ten kinds of lettuce, to transplant into our hoophouse for winter greens.
Last winter we tried the Osborne Multileaf lettuces compared to Salanova types, and were well pleased with the Osborne ones. And so we are growing more of those this winter, along with Tango, Panisse, Oscarde, Merlot and Red Tinged Winter. Next week I’ll sow another ten lettuces (some of the same and some others), along with Russian kales and senposai, more Yukina Savoy and the first round of mizuna and fancy frilled mustards, such as Ruby Streaks.
Next weekend (September 18-20) I will be speaking at the Mother Earth News Fair in Seven Springs, Pennsylvania. I”l be one of the Keynote Speakers, talking about Fall and Winter Hoophouses on Friday 4 – 5 pm on the Mother Earth News Stage. Then I will sign books in the MEN Bookstore immediatley following the workshop.
On Saturday 10 – 11 am on the GRIT Stage I will speak about Spring and Summer Hoophouses. That pair of workshops should give plenty of ideas for the whole year.
I’m also doing off-stage demos of tomato string-weaving (using a table-top model) twice a day at the New Society Publishers booth 104.
Because printing 600 handouts is out of the question (too many trees would have to die, and so on), I have made pdfs of my handouts to post here. Click on the links.
Fall and Winter Hoophouses Handout
Spring and Summer Hoophouses Handout
Sales of my book peaked during the holiday season (as also happened last December), so I conclude quite a few growers got a copy as a gift. I hope you are all happy with it! I also noticed that my reviews of Craig LeHoullier’s Epic Tomatoes and Jean-Martin Fortier’s Market Gardener have had a lot of visits, so many gardeners and growers will be curled up with a book, making plans for the next growing season.
I’ve also been catching up on reading, although if I had more time, I could give in to that urge even more! Last week I wrote a post for the Mother Earth News Organic Gardening blog, on Winter Vegetables in Your Hoop House and I firmed up a booking to present 3 workshops at the West Virginia Small Farms Conference February 26-28. On the Friday I’ll be presenting two new workshops back-to-back: winter hoophouse growing and summer hoophouse growing. Of course, I have mentioned these topics in other workshops I’ve presented. The winter crops feature in Cold Hardy Winter Vegetables (click the link to watch the slideshow). I won’t be presenting that workshop at Charleston (the WVSFC site) despite what I said a couple of weeks ago!
The summer crops featured in a presentation I gave at the Southern Sustainable Agriculture Working Group Conference “Practical Tools and Solutions for Sustaining Family Farms.” This year it’s January 14-17, 2015, in Mobile, Alabama. I wish I was going, but I decided it was too far away this year. I intend to go in 2016, when I hope it will be nearer Virginia. My summer hoophouse crops workshop for SSAWG was way back in 2009, before I really got to grips with slideshows! And now I have a lot more photos than I did then! And at WVSFC my Saturday workshop will be the ever-popular Succession Planting for Continuous Vegetable Harvests.
Meanwhile, this week in the garden, I have been taking my turn with the other crew members to harvest for our 100 community members. It takes about 3 hours each day to haul in enough fresh veggies for the masses. Outdoors we have kale, spinach, collards, leeks, cabbage and still some senposai, and the last dregs of celery and lettuce. The chard and the scallions have given up for now. Not dead, just resting. In the hoophouse we are harvesting salad mix, which includes some combination of baby lettuce mix, spinach, mizuna, Ruby Streaks, Bulls Blood beets, Tokyo bekana, Bright Lights chard and arugula). Each harvester gets to customize the mix as they like, so we don’t get the same thing every day.
We are also harvesting pak choy and Napa Chinese cabbage as well as baby turnips and turnip greens, radishes, tatsoi, Yukina savoy, and spinach for cooking. We are leaving the kale and the lettuce heads for later, when we have fewer other crops available (or if we are under snow). the hoophouse is a delightful place to work!
Pretty soon we will be dusting off our heat mat, plugging in the germination chambers, tipping the spiders out of the pots and flats and starting our first seedlings of 2015. We usually start with some early cabbage, lettuce, and mini-onions Red Marble in mid January, and follow up with early tomatoes (to plant in the hoophouse) the week after that. At that time we also start kale and spinach, although nowadays we start those in the ground in the hoophouse and move them out to the garden as bare-root transplants.
Recently I reported on which crops were still alive after two nights at 14F (-10C) and What’s still alive after two nights at 4F? We’ve now had the Polar Vortex, which brought us two nights at 4F, on 1/6 and 1/7. Then it got even colder.We got the Big Round 0F 1/22-1/23, then a few nights at 5F or 6F, and then the big insult: -4F 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.
Many of our strawberry plants look dead – very disappointing!
Our hardneck garlic and Polish White softneck tops are killed back to about one inch up from the mulch. Equally hardy, it seems.
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. After the 4F assault we still had life in the centers of the Winter Marvel, North Pole, Tango, Green Forest. Now 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 lost our second sowing of spinach in there to over watering and flooding, and we are really noticing the lack right now. We’re short on 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.
In January we have taken to sowing spinach, kale and collards in a hoophouse bed to transplant outdoors in early spring. We back this up with sowing some in flats if we don’t get good emergence for some reason. This year emergence is late. Is it just late, or is there a problem? We’re holding our breath for a few more days. . .
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. They planted kale, carrots, spinach, salad greens and arugula in their greenhouses for winter harvest. Their outdoor temperatures fell to -16F on 1/6 and 1/7. I imagine they’ve had worse since. They used mid-weight rowcover over their beds. Ben reports that baby greens and young spinach survived, as did their rosemary and their 3 fig trees (all farmers deserve some thrills!). They lost baby salad greens that had already been cut previously (all those cut edges didn’t do well). Crops in the outer beds were lost. The tips of full-grown kale leaves froze, but the plants survived.
In their unheated, single-skin plastic hoophouses, the soil froze down to 4″. They used two layers of mid-weight rowcover suspended over the crops. Despite this cold, tiny salad greens less than 1″ tall survived. Spinach survived under just one layer of rowcover. The carrot tops froze and the roots may or may not be marketable. The (uncovered) fully mature kale looks dead. The mature salad with two layers of rowcover didn’t survive.
From this experience, Ben points out that salad greens and spinach less than 1″ tall are very cold-tolerant. Spinach and kale once larger, benefit from more protection than they got this time. Beware the outer beds!
My own article in this issue is about matching crop spacing with desired goals, such as maximum yield, optimum size, or convenience for cultivation.
Andrew Mefford has written some greenhouse tips for hoophouse growers, including tomato grafting, trellising. Chris Blanchard has written the second part of his piece on growing herbs – this is about harvest and maintenance. Erin Benzakain has undertaken a 59-variety trial of celosia.
Recently I reported on which crops were still alive after two nights at 14F (-10C) and several others in the teens. We’ve now had the Arctic Vortex, which in our part of central Virginia, meant two nights at 4F, last 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.
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 Big Chill, to see what is still alive. We have Tyee spinach under rowcover, and Vates and Beedy’s Camden kale without rowcover. They are all still alive! There’s 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 are still alive. They will grow back if they have died.
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!
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.
When we placed our seed orders we gave up for this year on our quest for a reliable red cabbage of at least medium size and fairly speedy maturity (90 days or less). We’re having a red-cabbageless year. We’re still open to recommendations (OP or hybrid) – please leave a comment.
One of my ongoing topics of interest in the garden is how cold-tolerant various vegetables are. We’ve now had two nights at 14F (-10C) and several others in the teens. I took a walk round the frozen garden this morning to see what is still alive. We have Tyee spinach under rowcover, and Vates kale. The senposai is still alive, but some of the midribs have brown streaks. Sadly we don’t have any leeks this winter, as we lacked enough workers to tend them in late summer. We have a nice bed of Deadon cabbage, and I notice that some small heads of Melissa savoy that missed the bulk harvest are also alive. The Gunma cabbage stumps have some leaves and tiny heads still alive, but the Tendersweet are done in.
Our ongoing quest for a reliable red cabbage of at least medium size and fairly speedy maturity (90 days or less) yielded no success story this year. We grew Super Red 80 happily for many years, but then it stopped working for us – variable heads, slower maturity. If you have any recommendations (OP or hybrid) please leave a comment. We are working on our seed orders now, and this would be a great time to have some suggestions.
Back to today – our chard had all the leaves cut off in November, and seems to be dead. Some winters it hangs on later, if we leave some foliage to help it regenerate. We have also some years deliberately kept it alive for spring by using rowcover on it. We do that if we go into winter short of spinach beds.
The oats cover crop we sowed in August and early September look pretty much dead. All the broccoli looks 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 look to be in good shape. The Polish White softneck tops are considerably smaller and look like they are suffering. 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 is 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. Soon we’ll start on the heading Asian greens: pak choy, Chinese cabbage, Tokyo bekana and Yukina Savoy. The first sowing of tatsoi (9/7) is starting to bolt, so we’re clearing that. The second sowing (11/15) needs thinning to an inch. The first round of baby lettuce mix (10/24) is ready for its second cut. In a few days we’ll make a second sowing of that. I love working in the hoophouse on sunny winter days. This afternoon I plan to complete the transplanting of an 11/9 sowing of spinach. We just love the sweet nuttiness of winter spinach!
