No-Till Growers and Josh Sattin collaborated to post this Hoophouse Tips video interview of me talking about our hoophouse:
After a Best Ever day on November 7, 2019, when 876 people viewed my website (4,855 that week), December has been quiet. It’s not a big gardening month for most of us, and the month is full of holidays. And then there’s the urge to hibernate.
Nonetheless, I have been reliably posting every week, and you might have accidentally missed something, while entertaining the visiting aunts and uncles, or rushing to get the carrots harvested, or something involving food and drink. Here’s a chance to find the lost treasures!
Soil Tests and High Phosphorus Levels close behind at 9,503. High phosphorus is a worry for organic growers, especially those using lots of compost, as it can build up each year.
How to Deal with Green Potatoes at 8,613, with sustained interest through August, September and November. Obviously we are not the only growers with this problem, caused by light getting to the tubers.
We drove home seven hours from the Pennsylvania Mother Earth News Fair yesterday through the rain. The remnants of Hurricane Florence. We were among the lucky people. Earlier forecasts for Florence had the hurricane raging across central Virginia.
At the Fair, I gave two workshops: Fall and Winter Hoophouses and my new Lettuce Year Round, which you can view right here. Click the diagonal arrows icon to get a full screen view.
I’ve updated my Events page again, now that the September- April “Events Season” has hotted up. I’ve added in a couple of new ones and updated some others. Click the Events tab to find conferences and fairs near you, and be sure to come and introduce yourself!
I’m giving a Premium Workshop on Friday Sept 21, 3-4 pm Classroom 7. Click the link HEREto book for that.
Feeding the Soil
In this workshop I will introduce ways to grow and maintain healthy soils: how to develop a permanent crop rotation in seven steps, and why your soil will benefit from this; how to choose appropriate cover crops; how to make compost and how to benefit from using organic mulches to feed the soil. Handouts.
Book-signing Friday 4.15 – 4.45 pm.
On Saturday there are events all day from 10am to 5pm. $26 general admission.
Here’s the long version of one of the slideshows I presented on January 13 at the Future Harvest CASA conference. Since I got home, I updated my Winter-Kill Temperatures list, which appears in the slideshow. Compared to my list for 2016, there are a few differences, nothing major. We had some extremely cold weather, as I reported last week with some sorry pictures of lettuces. Now I have some photos of the outdoor crops too. The Vates kale had mixed survival, the rowcovered Reflect and Avon spinach are damaged but OK, the Tadorna leeks are battered but hanging in there (so are we!).
For several years I have been keeping records of how well our crops do in the colder season. I note each increasingly cold minimum temperature and when the various crops die of cold, to fine tune our planting for next year. We had some extremely cold temperatures of -8°F and -9°F (-22°C and -23°C) in early January 2018. We are in zone 7a, with an average annual minimum temperature of 0-5°F (-18°C to -15°C).
Unless otherwise stated, these are killing temperatures of crops outdoors without any rowcover. All greens do a lot better with protection against cold drying winds. Note that repeated cold temperatures can kill crops that can survive a single dip to a low temperature, and that cold winds, or cold wet weather can destroy plants quicker than simple cold. Your own experience with your soils, micro-climates and rain levels may lead you to use different temperatures in your crop planning.
Our double-skin hoophouse keeps night time temperatures about 8F (4.5C) degrees warmer than outdoors, sometimes 10F (5.5C) warmer. Plus, plants tolerate lower temperatures inside a hoophouse. The soil stays warmer and the plants recover in the warmer daytime conditions (it seems to be the night+day average temperature that counts).
In the hoophouse (8F warmer than outside) plants without extra rowcover can survive 14F colder than they could survive outside; 21F colder than outside with rowcover (1.25oz Typar/Xavan).
For example, salad greens in a hoophouse can survive nights with outdoor lows of 14°F (-10°C) without inner rowcover. Lettuce, mizuna, turnips, Russian kales, Senposai, Tyee spinach, tatsoi, Yukina Savoy survived a hoophouse temperature of 10.4°F (-12°C) without rowcover, -2.2°F (-19°C) with. Bright Lights chard got frozen leaf stems.
Lettuce hardy enough for a solar heated winter hoophouse in zone 7a (hardiest are in bold): Buckley, Ezrilla, Green Forest, Green Star, Hampton, Hyper Red Rumpled Wave, Marvel of Four Seasons, Merlot, New Red Fire, North Pole bibb, Outredgeous, Pirat, Red Cross bibb, Red Sails, Red Salad Bowl, Red Tinged Winter,Revolution, Rouge d’Hiver, Salad Bowl, Sylvesta bibb, Tango,Winter Marvel, Winter Wonderland.
35°F (2°C): Basil.
32°F (0°C): Bush beans, cauliflower curds, corn, cowpeas, cucumbers, eggplant, limas, melons, okra, some Pak Choy, peanuts, peppers, potato vines, squash vines, sweet potato vines, tomatoes.
27°F (-3°C): Many cabbage varieties, Sugarloaf chicory (takes only light frosts).
25°F (-4°C): Some cabbage, chervil, chicory roots for chicons, and hearts, Chinese Napa cabbage (Blues), dill (Fernleaf), endive (Escarole more frost-hardy than Frisée), some fava beans (Windsor), annual fennel, some mustards (Red Giant, Southern Curled) and Asian greens (Maruba Santoh, Mizuna, most Pak Choy, Tokyo Bekana), onion scallions (some are much more hardy), radicchio.
22°F (-6°C): Some arugula (some varieties are hardier), Bright Lights chard, large leaves of lettuce (protected hearts and small plants will survive colder temperatures), rhubarb stems and leaves.
20°F (-7°C): Some beets (Bulls Blood, Chioggia,), broccoli heads (maybe OK to 15F), Brussels sprouts, some cabbages (the insides may still be good even if the outer leaves are damaged), celeriac, celtuce (stem lettuce), some head lettuce, some mustards/Asian greens (Tendergreen, Tyfon Holland greens), flat leaf parsley, radishes (Cherry Belle), most turnips (Noir d’Hiver is the most cold-tolerant variety).
Large oat plants will get serious cold damage. Oats seedlings die at 17°F (-8°C)
Canadian (spring) field peas are hardy to 10-20°F (-12 to -7°C).
15°F (-9.5°C): Some beets (Albina Verduna, Lutz Winterkeeper), beet leaves, some broccoli, some cabbage (Kaitlin, Tribute), covered celery (Ventura), red chard, cilantro, endive, fava beans (Aquadulce Claudia), Red Russian and White Russian kales, kohlrabi, some lettuce, especially medium-sized plants with 4-10 leaves (Marvel of FourSeasons, Olga, Rouge d’hiver, Tango, Winter Density), curly leaf parsley, rutabagas (American Purple Top Yellow, Laurentian) if not covered, broad leaf sorrel, most covered turnips, winter cress.
12°F (-11°C): Some beets (Cylindra,), some broccoli, Brussels sprouts, some cabbage (January King, Savoy types), carrots (Danvers, Oxheart), most collards, some fava beans (mostly cover crop varieties), garlic tops if fairly large, most fall or summer varieties of leeks (Lincoln, King Richard), large tops of potato onions, covered rutabagas, Senposai leaves (the core of the plant may survive 10°F/-12°C), some turnips (Purple Top).
10°F (-12°C): Covered beets, Purple Sprouting broccoli for spring harvest, a few cabbages (Deadon), chard (green chard is hardier than multi-colored types), some collards (Morris Heading can survive at least one night at 10F), Belle Isle upland cress, some endive (Perfect, President), young Bronze fennel, probably Komatsuna, some leeks (American Flag, Jaune du Poiteau), some covered lettuce (Pirat, Red Salad Bowl, Salad Bowl, Sylvesta, Winter Marvel), covered winter radish (Daikon, China Rose, Shunkyo Semi-Long survive 10°F/-12°C), large leaves of savoyed spinach (more hardy than flat leafed varieties), Tatsoi, Yukina Savoy.
Oats cover crop of a medium size die around 10°F (-12°C). Large oat plants will die completely at 6°F (-17°C) or even milder than that.
5°F (-15°C): Garlic tops even if small, some kale (Winterbor, Westland Winter), some leeks (BulgarianGiant, Laura), some bulb onions, potato onions and other multiplier onions, smaller leaves of savoyed spinach and broad leaf sorrel. Many of the Even’Star Ice Bred greens varieties are hardy down to 6°F (-14°C), a few unprotected lettuces if small (Winter Marvel, Tango, North Pole, Green Forest).
0°F (-18°C): Chives, some collards (Blue Max, Winner), corn salad (mache), garlic, horseradish, Jerusalem artichokes, a few leeks (Alaska, Durabel, Tadorna); some bulb onions, yellow potato onions, some onion scallions, (Evergreen Winter Hardy White, White Lisbon), parsnips (probably even colder), salad burnet, salsify (?), some spinach (Bloomsdale Savoy, Olympia, Tyee). Walla Walla onions sown in late summer are said to be hardy down to -10°F (-23°C), but I don’t trust below 0°F (-18°C)
Crimson clover is hardy down to 0°F (-18°C) or slightly colder
-5°F (-19°C): Leaves of overwintering varieties of cauliflower die, Vates kale survives although some leaves may be too damaged to use.
-10°F (-23°C) Austrian Winter Field Peas and Crimson clover (used as cover crops).
-15°F (-26°C) Hairy vetch cover crop – some say down to -30°F (-34°C)
-20°F (-29°C) Dutch White clover cover crops – or even -30°F (-34°C)
-30°F to -40°F (-34°C to -40°C): Narrow leaf sorrel, Claytonia and some cabbage are said to be hardy in zone 3
-40°F (-40°C) Winter wheat and winter rye (cover crops).
In the hoophouse we are perhaps half way through our bed preparations. The Tokyo Bekana was the first crop we transplanted from our outdoor nursery bed, and it’s looking very sturdy now. We’ve also transplanted some Yukina Savoy and the first of the lettuces.
Cherry Belle radishes in the hoophouse, early October.
Photo Pam Dawling.
The crops we direct sowed in early September are growing well, and we are harvesting the radishes and some of the tatsoi and Bulls Blood beet greens (thinning to 6″ apart). The spinach is big enough to start harvesting but we haven’t needed to yet.
The newer sowings (the second radishes and the first brassica baby salad mix (mustards) have emerged and are ready to thin to 1″. Sometimes we use thinned seedlings as a salad garnish, but it takes more time than simply pulling them out, and it takes attention to keep them clean.
This summer we grew more cover crops rather than seed crops, which we have been growing in summer for several years, because we were short of workers. In the photo below you can see some healthy cowpeas I’m going to be pulling up later today, as well as some pulled up and dried buckwheat. We don’t dig our cover crops under, just let them die on the surface for as long as possible, shedding bits of dead leaf, then haul them to the compost pile. With the cowpeas, we hope to leave the nitrogen nodules from the roots, by ripping the plants up roughly!
These cowpeas have been cut back two or three times over the summer, to keep them manageable. At one point, they were black with sooty mold growing on aphid honeydew. We wondered if it was going to be a bigger problem, but after we cut the plants back, most of the aphids seem to have died. We also got a healthy population of ladybugs.
I gather readers are planning for winter, as many folks have been visiting my Winter-Kill Temperatures List of hardy crops. I update this list every spring, with the info from the previous winter. It’s useful for planning harvests based on forecast temperatures, and it’s useful for planning which winter crops will grow in your location, either inside or out.
On the same theme, I just discovered the WeatherSpark website which provides “The Typical Weather Anywhere on Earth”. Enter your nearest town or airport and you get clearly explained info with fascinating graphics of how the weather goes over the year in your locality. Note this is not a forecast site, it’s about average weather for each place. Useful to people who’ve recently moved and want to know what to expect this winter, or to new gardeners who haven’t paid so much attention previously. Or to those who want to check their assumptions (I really thought the wind was out of the west more of the time than records say). There are charts of high and low temperature, temperature by the hour each month, cloud cover, daily chance of precipitation (both rainfall and snowfall), hours of daylight, humidity, wind speed and direction and solar energy. A big help in making wise decisions. I know that climate change is going to cause havoc with averages, and we’ll need to learn to become better weather forecasters individually, and to use soil temperature and other metrics to decide when to plant. But this website explains things well.
The October Growing for Market is out. Flower farmer Erin Benzakein writes about getting to grips with the marketing side of running a farm. She encourages farmers to get good photos, step out from behind the camera, and dust off their website. I could use some of this advice! (I’ve been very busy writing a hoophouse book, and have necessarily paid less attention to giving presentations and to rejuvenating this website!
Kai Hoffman-Krull writes about on-farm trials of bio-char. I’m looking forward to reading that. Jesse Frost writes about winter CSAs and profiles some he visited. Chris Bodnar covers Italy’s thriving agricultural co-ops and asks if this could be a model for the next phase of the locally-grown movement. Lastly Zach Loeks offers the first of a two-part series on Transitioning to a permaculture market garden.
The September/October issue of Organic Broadcaster is also out. Articles include attending to soil health to improve production; the top reasons customers buy organic foods (accountability, environment, health); interseeding cover crops in cash crops; an interview with farmers in the MOSES Farmer-to-Farmer Mentoring Program; designing an efficient pack shed; and selecting the right meat processor.
Lastly, the campaign www.keepthesoilinorganic.org has posted a letter a letter recently sent out by farming mentor Eliot Coleman about the travesty of allowing hydroponics to be certified as Organic. Hydroponics is a system of growing plants anchored in holes in plastic tubes, or in blocks of inert material, and feeding them with a liquid solution of things that work to produce mature plants. The arrogance of imagining we know everything a plant needs is astounding! The idea that all the many complex ingredients of soil can be replaced with a synthetic concoction is staggering!
Eliot Coleman’s letter includes these quotes:
Organic farming is best defined by the benefits of growing crops on a biologically active fertile soil.
The importance of fertile soil as the cornerstone of organic farming is under threat. The USDA is allowing soil-less hydroponic vegetables to be sold as certified organic without saying a word about it.
The encouragement of “pseudo-organic” hydroponics is just the latest in a long line of USDA attempts to subvert the non-chemical promise that organic farming has always represented. Without soil, there is no organic farming.
Eliot Coleman will be a speaker, along with Fred Kirschenmann, Enid Wonnacott, Jim Riddle, Will Allen, Jeff Moyer, Dave Chapman, Anaise Beddard, Lisa Stokke, Tom Beddard and Linley Dixon at the Jacksonville Rally of the Keep the Soil in Organic movement. Oct 31, 2017 at 12:45 pm – 2:00pm EDT. Omni Jacksonville Hotel, 245 Water St, Jacksonville, FL 32202, USAThis Rally will be a gathering of organic farmers and eaters from all over the world. The march will begin at the Omni Jacksonville during the lunch break from 12:45 to 2 PM on Tuesday, the first day of the NOSB meeting. There will be a 5 minute march to The Landing from the Omni. Lunch will be available at the Rally. For more information, call Dave Chapman at 802-299-7737.