Book Review, The Greenhouse and Hoophouse Grower’s Handbook, by Andrew Mefferd

The Greenhouse and Hoophouse Grower’s Handbook,  Organic Vegetable Production Using Protected Culture. by Andrew Mefferd. Chelsea Green.March 2017, $34.95. ISBN 978-1-60358-637-5

I was lucky enough to be asked to write an endorsement for this book, and was sent an uncorrected proof to read. Now I have the full color, published version, and I’m poring through it once again. Andrew Mefferd is the editor and publisher of Growing for Market magazine that I sometimes write for. Prior to that job, he worked at Johnny’s Selected Seeds, in the research department for seven years. Born in Virginia, he apprenticed on farms in six states on the west and east coasts, then farmed in Pennsylvania. He now farms in Maine, and has a good appreciation for the difference a different climate can make.

This is not an “Everything you always wanted to know to get started with a hoophouse” book, nor a compendium of greenhouse crops, pests and diseases. On the contrary, this book focusses down on the precise details of successful practices to grow what Andrew has determined to be the eight most profitable crops using protected culture: tomatoes, peppers, cucumbers, eggplant, lettuce, greens, microgreens and herbs.

This is a book to come back to each time we want to know more about one of his topics. If I were about to launch into microgreens, I would follow Andrew’s methods. I tend to read quite widely on vegetable growing topics and I’ve read some very fussy time-consuming microgreens-growing instructions for home gardeners. I haven’t seen another book be so down-to-earth with an efficient and professional growing method that uses only simple tools and supplies. Those wanting to grow microgreens in quantity, and make a living from it will find plenty of information to get started or to fine-tune their operation.

The part of the book I’m most excited about right now is the information on what plants need at different stages of growth, in terms of balance between temperature, humidity as it affects transpiration, daylength, light intensity, carbon dioxide, oxygen, water and nutrients; and how to use this information for “crop steering” – adjusting conditions to select for leaf growth or fruit development. Here are the details to get it right. I once got a light meter to compare the light transmission through clouded old glass and new glass (I wanted to know if it was worthwhile to replace the glass in our greenhouse). But then I didn’t know how to use the information. Now I know that 1% less light will lead to about a 1% lower yield. Specific information like this can be hard to dig up bit by bit on the web. Here the gold nuggets have been screened for us, and the mud left behind.

The book starts off with a sixty page section on the basics of protected culture: the why, what and how of the various options of structures and utilities you might be choosing among, with a chapter on economics and efficiencies. The main part of the book then dives into the specific practices that help the eight crops do best. Chapters on propagation, pruning and trellising; temperature control and crop steering; and grafting are applicable to many of the recommended crops. Next follow chapters on each of the crop groups, and appendices on hydroponics, pests and disease and tools and supplies.

Andrew is obviously a very attentive farmer, and one who keeps good records. And here we can all benefit, whether experienced growers looking to improve our game, or beginners wanting to grasp success from day one. Serious backyard gardeners could use this book too, not only commercial growers. Facts are facts, results are results. Not everyone will want to follow all of the recommendations immediately or perhaps ever. In our hoophouse in Virginia, we grow two beds of early tomatoes in our hoophouse with just enough trellising to keep them upright, and minimal pruning. As soon as our outdoor tomatoes are producing well, we pull out the hooophouse rows. Our climate doesn’t warrant keeping them in the hoophouse, and in fact, it may get too hot in there for them. Our climate is full of fungal diseases, so crop rotation is very important to us, and the sooner we don’t need tomatoes in the hoophouse, the sooner we can remove them and their fungal spores!

But I do remember growing tomatoes in a glass greenhouse in northern England, and how we cherished those plants! I had started to experiment with side-grafting 25 years ago, in hopes of having sturdier tomatoes. We pruned and twined, and every ripe tomato was precious to us. It was late September when I moved to Virginia, and I helped the garden crew harvest Roma paste tomatoes, which were grown sprawled on the ground. That in itself was a shock – gosh these people don’t hold their tomatoes in very high regard, they let them rot on the ground! The crew member working next to me shocked me further: “Stomp on the green ones” she muttered under her breath. Apparently so great had been the harvest of these paste tomatoes that the crew was exhausted from harvesting and wanted to be done!

So, select the sections of Andrew’s book that speak to your needs and your climate. There’s something for everyone. You don’t need to abide by it all to want the book. It will easily pay for itself if you find only one new practice to adopt this season. But read the whole book anyway, and you can develop a fuller understanding of the big picture, a new management strategy and a set of skills to deal with the challenges that arrive unbidden. Andrew has tested all these practices as a small-scale grower himself, and he does this because he’s a passionate supporter of local food, sustainably grown, and sees protected cropping as a way to increase local food production by increasing on-the-ground crop insurance in the face of the unpredictable.

Young tomato plant in our hoophouse in April.
Photo Kathryn Simmons

Lettuce in April

Spring lettuce bed.
Photo Wren Vile

We’re on the brink of starting to harvest our first outdoor lettuce, switching over from the last of the baby lettuce mix in the hoophouse. Our goal for this transition is April 15, but naturally the exact date will depend on the weather in the spring, the coldness of the late winter, the rate at which we are eating lettuce and other factors beyond the grower’s control.

Hoophouse baby lettuce mix. Photo Kathleen Slattery

We make three sowings of baby lettuce mix: 10/24 to harvest early December to early March (after we’ve cut it several times, and it is starting to tun bitter); 12/31 to harvest from late February till the end of March Later if it doesn’t get bitter from hot weather); and 2/1 to harvest mid March to the end of April. This year the #2 sowing is still edible in mid April, so we have two patches feeding us for a little longer.

Our winter salad mixes are very popular, but we can only continue with those as long as the spinach and the salad brassicas hold up. Part of me is always sad to stop eating salad mix, but the other part welcomes the juicier, crunchier, tastier head lettuce. Baby lettuce mix is very pretty, but honestly I find it a bit short on flavor and texture! It’s the other ingredients in the salad that make it interesting for me, especially spinach.

The first outdoor lettuce were sown 1/17, planted out 3/9, to feed us 4/15 to 5/8, when the second sowing should be ready. We cover these with rowcover on hoops when we transplant, for about a month, or until the weather seems settled at a reasonable temperature.

Our raised beds outdoors are 4 ft wide, with 1 ft paths. we plant four rows of lettuce, spaced 12″ apart, and plant about 120 from each sowing. That usually fills a third of a 90 ft long bed, so we have 3 different plantings in each bed of lettuce. We continue at this pace until our last outdoor plantings around the fall equinox.

This spring we are going to continue the salad mixes a bit longer by harvesting the outdoor lettuce by the leaf. We have lots of really good looking spinach to mix in, and the last few mizuna and ferny mustards. We used to only sow these twice, 9/24 to transplant in the hoophouse, and 11/9, which feeds us until late March. We added in a third sowing of mizuna and ferny mustards 2/1 which we harvest 3/24 to 4/23 approximately. That extra month is really worth having!

We also have a short row of Sugar Ann snap peas in the hoophouse (sowed 2/1) that we like to snip into thirds and add to salad mix. This makes for a nice little surprise for everyone. We couldn’t feed a hundred on 50 ft of snap peas! These are an incentive to keep the salad mixes going while the peas are being harvested.

Sugar Ann snap peas in our hoophouse, a month earlier than outdoor peas.
Photo Bridget Aleshire

 

Growing for Market, Sweet potato propagation and yields

The April issue of Growing for Market is out! For those of you growing sweet potatoes, Andrew Schwerin from NW Arkansas has written an interesting article. I’ve written about starting sweet potato slips before and I have a slideshow that includes three methods of  starting your own slips.  He and his wife Madeleine grow 1500 feet of sweet potatoes each year, a third of their growing area.

I was interested to note their reasons for growing so many sweet potatoes (apart from the obvious fact that they can sell that many). Sweet potatoes are not a big moneymaker in terms of the space occupied. Here at Twin Oaks we pondered similar issues this winter when deciding which crops to grow.  We worked down a list of 25 factors, deciding which were important to use. We chose our top handful of factors and then worked down a list of crops we might grow, awarding points (or not!) for each factor for each crop. This helped us narrow down what to focus on this year. And yes, we are growing sweet potatoes! I wrote about this in Growing for Market in February 2017.

These growers listed the following factors as their reasons to grow sweet potatoes:

  • Sweet potatoes produce well in our soil

  • They aren’t troubled by intense summer heat

  • Extensive vines will smother most weeds

  • Few pest or disease issues

  • Most of the labor is in early October, between intensive harvests of summer and fall crops

  • They store long-term for steady sales through the winter

Sweet Potato harvest at Twin Oaks. Photo McCune Porter

They like Beauregard, and wanted to try using the single node cutting method, as advocated by Anthony and Caroline Boutard – see my Sweet Potato slideshow for details. Initially they were excited about the single node cutting process, as their roots produced exponentially more growing shoots each week. OK, maybe exponential is a bit of an exaggeration, but it gives the sense of it. Because they had so much propagation material, they started making 5-node slips, rooting clusters of cuttings in pots of compost, 3 nodes in the soil for roots, 2 nodes above ground.

Some of their single node cuttings failed to thrive, both in the trays and in the field, so they developed a 2-node cutting system instead, and also used their five-node slips. And so they had a trial of three sweet potato cutting methods, with plants in different 100 ft beds. In the past (using the regular slips method) they have averaged yields of 500-600 lbs of sweet potatoes per 100 ft bed, with a range from a poor 250 lbs to a few successes with 1000 lbs/bed. Of course, yield is not the only important feature of a market crop, although understandably it has a high profile for those growing 1500 row feet for sale.

At harvest, they found that their single-node sweet potato plants were producing a couple of hundred pounds per 100 ft bed. The 2-node beds produced about 500 pounds per bed, of relatively few, very large (6 – 20 lb) sweet potatoes. The plants with 3+ nodes in the soil gave more reasonable sized potatoes. They tend to get jumbos, so they have started planting closer (10″) to tackle this – not many customers want jumbos.

In his article in Growing for Market,  Anthony Boutard pointed out that single-node cuttings do produce fewer tubers which are larger and better formed. This is a big advantage for growers in the north, but less so in the south. The Arkansas growers have found that the 2-node cuttings are even better at this tendency in their location, which is much further south than Anthony Boutard’s farm.

Beauregard sweet potatoes saved for seed stock.
Photo Nina Gentle

Other articles in this month’s Growing for Market include Managing a cash crisis
How to climb out of the hole by Julia Shanks, the author of The Farmer’s
Office. Farmers deal with a very seasonal cash flow, and may well have gone into farming with good farming skills but not good business skills. Julia writes about four rules for getting out of a financial hole.

  1. Quit digging (don’t incur any more inessential expenses).
  2. Keep the dogs at bay (communicate with your creditors about how you plan to pay, and how you plan to keep producing the goods).
  3. Climb out (increase revenue in as many ways as possible).
  4. Get your head out of the sand (don’t panic, face realities, be proactive).

She goes on to list 10 ways to protect yourself from getting in such a hole again.

Sam Hitchcock Tilton has an article about cultivating with walk-behind tractors, ie, weeding and hoeing with special attachments. There are some amazing walk-behind
weeding machines (manufactured and homemade) throughout the world. There
is an entire style of vegetable farming and scale of tools that have been forgotten, in between tractor work and hand growing – the scale of the walk-behind tractor. The author explains how commercially available tools can be adapted to work with a BCS or a carefully used antique walk-behind tractor.

Mike Appel and Emily Oakley contributed Every farm is unique, define success your own way. Money is not the only measure. Quality of life, family time, and personal well-being are up there too, as are wider community achievements. Farming is equal parts job and lifestyle, and the authors recommend having a strategic plan for yourself and the farm, which you update every couple of years to pinpoint goals and the steps you need to take to reach them.

Cossack Pineapple Ground Cherry
Photo Southern Exposure Seed Exchange

Liz Martin writes about husk cherries (ground cherries) and how to improve production of them, to make a commercial crop viable. Who would have guessed that hillling the beds before planting can make harvest so much easier, because the fruits roll down the sides?

Judson Reid and Cordelia Machanoff wrotea short piece: Fertility tips and foliar testing to maximize high tunnel crops, and Gretel Adams wrote about  Scaling up the flower farm. Many of the ideas also apply to vegetable farms.

Mother Earth News post, Organic Broadcaster, Jamaica trip

Hoophouse early squash planted in the middle of a bed of winter chard.
Photo Bridget Aleshire

I wrote a blog post for the Mother Earth News Organic Gardening blog on Hoophouse Intercropping in Spring.

We transplant our tomatoes, peppers, squash and cucumbers into the middles of the beds of winter crops. We pull out the middle rows, dig holes, add compost and transplant. Initially the rows of winter greens to the south of the new plants shade and shelter them a little, which helps them settle in. The next week we harvest out the greens on the south side of the new crops, then after that (but less urgently) the row on the north side.

Hoophouse peppers transplanted in the north hoophouse bed among lettuce mix.
Photo Bridget Aleshire

3/15 is our usual tomato planting date, 4/1 we planted squash. 4/5 we’ll put the cucumbers in and 4/7 the peppers. We used to plant the hoophouse peppers earlier but it’s such a struggle keeping them warm enough as seedlings in the greenhouse, that we moved a week later. It’s just not worth having stunted pepper plants!


The March/April Organic Broadcaster is out too. Phew it’s hard to find enough reading time in spring! There are articles about the Organic check-off program (discussed at the MOSES Conference), information about policy work for the National Organic Program, and their “Ask a Specialist” column answering a question about “fast, inexpensive greenhouse space.” The answer was souped-up 10 x 60 ft caterpillar tunnels, including heated benches for starting plants. Other articles address organic grain production, humane mobile houses for poultry, a profile of the MOSES Farmers of the Year, Hans and Katie Bishop, solar panels on small farms, diverse meat CSA farms, as well as news from the conference. Something for everyone!


I’m volunteering with the Jamaica Sustainable Farm Enterprise Project. Here’s a bit more about the project:

The people of Jamaica and the greater Caribbean region have long been buffeted by  natural and human-caused disasters that have left them in a state of economic, social, and environmental crisis. Jamaican  people are vulnerable due to national dependency on unaffordable, less healthy, imported food, lost skill sets needed to produce certain crops without expensive chemical inputs, and natural disasters that wipe out farmers crops with regularity. The Parish of St. Thomas and the other eastern parish of Portland have systemically been the most forgotten and underdeveloped parishes in Jamaica for over a century.

St. Thomas is a farming parish. However, since the liberalization of the banana industry by the European Union and NAFTA all the banana plantations have closed leaving few agricultural avenues for profitable employment in the parish. Many of the people of St. Thomas still rely on small cash crops and seasonal tree crop production for their livelihood.

JSFEP aims to focus on local sustainable production to increase food security and help develop high value internal and export markets to increase agricultural profitability. Permaculture and organic (POF) systems provide solid foundations for these solutions.

I’ll be going to St Thomas parish (click for a map) from 5/11 to 5/22, providing training in vegetable crop planning. JSFEP partners The Source Farm, a multi-cultural, intergenerational eco-village, located in Johns Town, in the parish of St. Thomas.  You can see a slideshow at their website. And You Tube has a short video The Source Farm Foundation Ecovillage.

Well, I’m out of time this week, as I need to get my laundry off the line and spray the aphids in the greenhouse and hoophouse with soapy water.

Transplanting into hay or straw mulch, organic myth-busting, keep soil in Organic

Hopefully the really cold nights are behind us. We had 20F last Wednesday night/Thursday morning 3/23. We are getting ready to transplant spring cabbage and broccoli. I wrote a bit about broccoli planting last spring (mostly about varieties and planting alyssum to attract beneficial insects) and in spring 2015. 

Flats of broccoli seedlings in our greenhouse in early March.
Photo Wren Vile

Here I’ll say more about transplanting into hay or straw mulch, which I have also written about for Mother Earth News. Transplanting into rolled out or pre-spread straw or hay from small square bales is quicker, easier and more effective than fitting the mulch around the transplants after you’ve planted them.

We bale hay into big round bales, and move them around with the tractor and forks or a rear bale spike (spear). We plan our beds to be 5′ apart on centers and our rows to be 5-5½’ apart (tomatoes, for example) . We prepare our beds and get the mulch dropped off at the uphill end (even a small slope is helpful!).

When we plant garlic in November, as soon as we’ve planted and covered the cloves with soil, we unroll the bales over the top of the beds.

Using mulch helps control weeds, and reduces the weed seed bank, which is the name for the store of weed seeds already in the soil, that will otherwise grow in the future. “One year’s seeding, seven years weeding,” is a wise and rueful gardener’s saying. Only perennial grasses and a few other “running” perennials will come up through a thick layer of hay. Plastic mulches, while they do deal with weeds, actually raise soil temperature. This is an advantage for warm weather crops, but not for brassicas! If using organic mulches for warm weather crops, it is often best to wait four weeks after transplanting, cultivate to remove one round of weeds, then roll out the mulch. This avoids cooling the soil which would slow growth down and delay harvests. If you’re waiting for watermelons, this is too sad! All kinds of mulch also reduce rain splash, helping prevent fungal leaf diseases.

Organic mulches have some advantages over plastic mulches. They keep the soil damper, which can mean higher yields and less need to water. They also keep temperatures lower in summer, an advantage for cool-weather crops, like broccoli and cabbage. Organic mulches improve the soil structure and increase the organic matter. The number of earthworms in the soil at the end of the season can be twice as high as under plastic mulch.

Rolling hay over newspaper for a new strawberry bed.
Photo Luke Stovall

There is a myth that organic mulches lock-up nitrogen from the soil. This could happen with soils which are very short on organic matter and micro-organisms. It does happen if fresh high-carbon sources, such as straw or hay, are incorporated into the soil. In my experience, surface mulches have not caused nitrogen shortages to the crops they mulch. Our soil is very fertile, and we do what we can to encourage soil micro-organisms to multiply, so that they can readily digest what we add to the soil. The longer-term effect of high-carbon mulches can be to increase the soil nitrogen. The micro-organisms feeding on the carbon die and decompose, and they are a high-N source!

If you are buying in straw or hay and need to watch costs, you could spread the organic mulch over a double layer of newspaper. You’ll only need half as much hay or straw compared to mulching with the straw or hay alone. The final result is only half as deep, which is an advantage when transplanting small plants, which could get lost in deep organic mulch. I believe the inks used on regular newsprint are not toxic. We avoid using glossy paper with colored inks, because of concerns about toxicity of the coating on the paper as well as the inks.

Spring cabbage planted in hay mulch, a few weeks after transplanting.
Photo Kathryn Simmons

We grow our own hay, so we know it is unsprayed – there is a danger from pyridine carboxylic acids, a class of broadleaf herbicides which persist through composting and even through the digestive systems of livestock, and can kill or seriously damage food crops and flowers. Grazon is one brand; picloram is the plant growth regulator it contains.

Our hay is not the perfect mulch, as it does have some weed seeds, and sometimes mold. (Our garden gets the hay which is not good enough for the cows to eat.) If you have the choice, unsprayed straw is better than hay, as it won’t have many weeds. We don’t live in a grain-growing area, so there is no local straw for sale.

We remove the twine (if it hasn’t already rotted and fallen off) and study the end of the bale to figure out which way it will unroll. This can be surprisingly unclear. If we have to turn the bale, or maneuver it to line up, we might have three people do that. Once it’s rolling, two people can manage to unroll a round bale of hay. We spend some time at the end using wheelbarrows to move hay from the thick places to the thinner spots.

For transplants we do what we call “making nests” in the hay. Two people work opposite each other, across a bed, as we plant two rows of broccoli or cabbage. One of the people has an 18″ stick to measure the  center-to-center plant spacing. The second person doesn’t measure, but staggers their row compared to the first person’s row, making a zig-zag to match the pattern. Both people aim to stay about 16″ from the edge of the bed, so the rows are evenly spaced across the bed. Using two hands, they pull open the hay, down to soil level. The “nest” needs a diameter of about 4″, for easy transplanting. We either make all the nests before we start planting, or we have two pairs of people, with the nesters moving faster than the planters. We want to get the plants in the ground quickly, and minimize the time they are out in the field wilting in the flat.

Each planter works along a row, transplanting into the exposed soil in the nests, firming the plants in and watering from a can every 10-20 plants (depending how hot or windy it is). Another crew member pulls the hose and wand along the aisles and gives all the plants a generous second watering. After the hose watering, someone pulls the hay around the stems at ground level.We call this ” tucking the plants in”. If plants are  “untucked”, this is the signal to the Hose Waterer that the plants need water.  When they are all tucked in along a section of a bed, it is the signal to those unrolling row cover to go ahead and cover. Our system is almost disaster-proof, as it includes indicators about the next task needed.

To have a long broccoli harvest period, we use several varieties with different days-to-maturity, and two sowing dates. This gives us the longest possible harvest period before it just gets too hot for pleasant-tasting broccoli.

A bed of early spring cabbage, planted into hay mulch.
Photo Kathryn Simmons


The Organic Trade Association has published a set of 33 little posters putting solid information out there, and busting some myths about organic agriculture . Here’s one with a photo on our cabbage theme.

The items are free to download, for any healthy food related events you might be organizing. Or just go and read them, so that next time someone asks you a question about organic farming, you’ll have the answers at your fingertips.


And talking about what’s allowed in Organic certification, one controversial practice is hydroponics, where plants grow without soil, in a liquid including nutrients (the nutrients people are aware the plants need). Another is aquaponics where plants grow without soil, in a liquid where farmed fish have been growing.

There is a “Keep the Soil in Organic” movement, which advocates for Organic certification requiring plants to be grown in soil, not water-plus-some-nutrients. Dave Chapman sent me this message asking for support for the National Organic Standards Board on 3/27/17:

“The NOSB needs our help.

The NOSB meets in Denver in three weeks to debate whether a healthy soil is the foundation of organic farming.

We have champions on the NOSB fighting for us, but they need to hear from you. They are facing tremendous pressure from professional lobbyists in this battle. Lee Frankel, one of the chief lobbyists for the hydroponic coalition, stated in an editorial last week that organic hydro is now a billion dollar a year industry. This explosive growth happened in just 7 years since the NOSB recommended that hydroponics has no place in organic certification. That recommendation was opposed by the USDA, and hydro has been welcomed into organic certification. The hydro industry sees organic as their economic gold rush. And they are only getting started.

Please submit a comment to the NOSB (National Organic Standards Board) letting them know that organic must be based on the fertility of a healthy soil ecosystem. Don’t let organic be destroyed.

Comments are due by this Thursday 3/30 at midnight. Do it now.

Click Comment Now!  “

No time to lose on that one! Big hydroponic “organic” industries have lobbied and got included as certifiably Organic, when most of us realize that growing food without soil is the opposite of Organic, with or without a capital O.

Pennsylvania farmer Tom Beddard speaks out on the soil in organic at the Rally In The Valley. “You can tell it was grown in the soil because it tastes better!”

Hoophouse slideshow, Ruminant podcast, potatoes planted

Here’s my updated Spring and Summer Hoophouse slideshow, that I promised all the people at my Organic Growers School workshops. I rearranged the slides in what I think is a better order and revised the resources section.


The Farmers Aren’t All Right.
Podcast from the Ruminant

I also took part in an interview with Jordan Marr for a podcast with The Ruminant: Audio Candy for Farmers, Gardeners and Food Lovers. It’s about farmers’ struggles with mental health problems, trying to cope with the many and varied stresses, while the public wants farmers to appear competent and blissful with all that time in the Inspiring and Nurturing Outdoors.

“Farming is tough work. The unpredictability of the job and the pressure to present a curated, bucolic version of the work can easily lead to various kinds of mental health problems: despair, feeling overwhelmed or like a failure, or even depression. In this episode, co-produced with Jessica Gale of Sweet Gale Gardens, we discuss the prevalence of mental health problems among farmers, and how to address them.” Jordan Marr

As well as Jessica Gale, the episode includes discussion of Professor Andria Jones-Bitton’s work and interviews with Jean-Martin Fortier of The Market Gardener and Curtis Stone of The Urban Farmer.


The March issue of Growing for Market is out. Nothing from me this month (I have articles for May and June/July coming up). In this issue. There are articles about No-till vegetable farming (Conor Crickmore at Neversink Farm, in the Catskill Mountains of New York), and Bio-integrated farm design by Shawn Jadrnicek, co-author with Stephanie Jadrnicek, of The Bio-Integrated Farm: A Revolutionary Permaculture-Based System Using Greenhouses, Ponds, Compost Piles, Aquaponics, Chickens and More. Lots of water in this book, and very practical. There’s an article on A DIY mobile cooler for moving and storing perishable foods  – an insulated trailer using Cool-Bot technology by Cary Rivard, Kansas State Research & Extension Horticulture & Forestry & Extension Vegetable & Fruit Crop Specialist. Karin Tifft has written The “other” reasons to grow in a greenhouse: climate, light, good use of space, reduced wastage of produce, energy conservation and more. Andrew Mefferd, the editor has written on growing cucumbers umbrella style under cover. Finally, Debra Prinzing writes on Making your mark with local branding.


Chitting seed potatoes ready for planting.
Credit Kati Folger

And here at Twin Oaks, we planted our spring potatoes yesterday, after pre-sprouting (chitting) the seed potatoes for a couple of weeks. Soon we hope to see the potato shoots emerging from the soil.

Potatoes emerging in spring.
Photo Kathryn Simmons

Hoophouse seasonal transition to tomatoes, peppers, squash, cucumbers

This past weekend I was at the Organic Growers School spring conference in Asheville, NC. I presented my workshop on Spring and Summer Hoophouses twice. This link will take you to a blog post where you can get the handout. An older version of the slideshow is at this SlideShare link. Later this week I will tweak the presentation a little and upload the revised version. It wasn’t very spring-like in Asheville. We got 3″ snow, but gardeners and farmers are a hardy lot, and attendance was still good. My workshops were packed (the room was quite small).


Young tomato plant in our hoophouse.
Photo Kathryn Simmons

Now I’m home and we had snow in the forecast for Monday night, but got ice pellets instead. The worst of the weather passed us by. It’s still very cold though, and so we are delaying transplanting our early tomatoes in our hoophouse, which we had scheduled for 3/15 and 3/16. The photo above shows where we’re headed: sturdy transplants in the middle of the bed, with wire hoops to hold rowcover on cold nights. Here’s where we are now:

March hoophouse bed prepared for tomato planting.
Photo Wren Vile

When we make the transition from hoophouse winter crops to early spring crops, we don’t clear the whole bed. First we harvest out the greens down the middle of the bed, then measure and dig holes every two feet and put a shovelful of compost in each hole. Within a couple of weeks after transplanting the tomatoes, we harvest the greens on the south side of the bed, as they will block light from the new crop. After that we harvest the greens on the north side. This allows us to keep the greens later, which covers the time (the Hungry Gap) until the new spring plantings of outdoor greens start to produce.

Tomato transplants in March, ready to plant in our hoophouse in milder weather.
Photo Wren Vile

Meanwhile the tomato transplants are in pots in our greenhouse, where we can keep them warmer at night with rowcover. Our greenhouse stays warmer at night than our double-poly hoophouse. It has a solid north wall and double-pane glass windows (old patio doors).

We use the same method for our peppers, cucumbers and yellow squash, transplanted 4/1. In the photo below you can see the winter crop of Bulls Blood beets, which we grow for leaves for salad mixes, discarded beet stems, young squash plants and one of the wire hoops that hold rowcover on freezing nights.

Young summer squash plants in the hoophouse, surrounded by Bulls Blood beets.
Photo Kathryn Simmons

In the hoophouse we have three crop seasons:

  1. winter crops planted in the fall, harvested November to April (some spinach to May)
  2. early warm weather crops planted in March and April, harvested June and July (peppers to November)
  3. high summer crops planted in July and harvested August to October.

 

Lettuce for March and all year

Bronze Arrow lettuce is a beautiful and tasty early spring variety.
Photo Bridget Aleshire

We’re continuing to have enough lettuce. We have pulled the first baby lettuce mix in our hoophouse, and have started pulling some heads in there.  Of course, we want to harvest the hoophouse head lettuce before it gets too bitter, but we also don’t want to get too far ahead with the harvesting and run out! Our second baby lettuce mix is now ready for cutting, and the third sowing is not far behind.

March 9 is our goal for a transplanting date outdoors for our first 120 heads of lettuce (about one week’s worth for 100 people). We sow four varieties each time, some green, some red, different shapes and textures, different numbers of days to maturity. This way we hope to have a constant supply, and hedge our bets if something goes wrong with one variety.

In our first sowing we have Parris Island green romaine, Buttercrunch green bibb, and Hyper Red Rumpled Wave, a very red leaf lettuce, as well as Bronze Arrow, shown above. Our second sowing includes Cosmo, another green romaine, Star Fighter, which I wrote about last June, Oscarde, a red wavy leaf lettuce and one of our work-horses, Red Salad Bowl. Our third sowing has Panisse, a green wavy-leafed variety, Revolution, a red leaf lettuce, Swordleaf, which I wrote about last spring, and green Salad Bowl.

Ezrilla Tango-type one-cut multileaf type lettuce
Photo High Mowing Seeds

Buckley red oakleaf one-cut multi-leaf lettuce.
Photo High Mowing Seeds

Our fourth sowing includes New Red Fire and three Eazyleaf lettuces ( Ezrilla, Hampton and Buckley) sold by High Mowing Seeds. We are simply trying these out this spring, to find out if we want to grow them next winter. In our climate these are unlikely to stand for long in the spring, and much more likely to grow well in our hoophouse in winter.

 

Hampton one-cut multi-leaf lettuce.
Photo High Mowing Seeds

These are varieties that produce lots of small leaves (no big leaves) enabling growers to get an instant salad by cutting a whole head. We are more likely to harvest them multiple times, taking some leaves each time. It’s exciting to see more lettuces of this type on the market. I wrote previously about Osborne’s Multileaf lettuces and Johnny’s Salanova varieties.

Here’s a link to our Lettuce Log, our schedule of lettuce planting and harvesting dates, that provides a succession of outdoor lettuce from April to November:

http://file:///X:/GARDEN/Planning/Lettuce%20Log%202017%20in%20Htm.htm

Gardening is not all about lettuce! We have sowed two beds of carrots outside and also a bed of turnips (Purple Top White and White Egg), with a row of radishes to pull before the turnips need the space. And we are still “recovering” from transplanting 3600 spinach plants. They are all doing well, despite my mix-up about which varieties were intended to be planted in which bed. We are comparing three varieties this spring: Tyee, Avon and Reflect.

Purple Top White Turnips.
Photo Small Farm Central

White Egg Turnips.
Photo Southern Exposure Seed Exchange

Lettuce in February, Growing for Market, open seed flats

Baby lettuce mix in our winter hoophouse.
Photo Twin Oaks Community

We still have plenty of lettuce to eat, although our first sowing of baby lettuce mix in the hoophouse has come to its bitter end, and the second sowing isn’t quite ready (I think we sowed it a bit later than intended). We are still harvesting leaves from the large lettuce we transplanted in October.  Soon we’ll have the second and third baby lettuce mix sowings to bring a welcome change. We are about ready to transplant our first outdoor lettuce, to feed us mid-late April.

Here is a month-by-month planting and harvesting narrative for our hoophouse lettuce in Zone 7, from September to April:

September: Sow cold-hardy varieties in the second and third weeks (outdoors or in your greenhouse) to transplant into the hoophouse at 4 weeks old .

October: 4 weeks after sowing, transplant those lettuces at 8” spacing to harvest leaves from mid-November to early March, rather than heads. In late October, sow the first baby lettuce mix, for up to 8 cuts from early December to late February, and sow a small patch of “filler lettuces” to replace casualties in the main plantings up until the end of December.

November: 11/9 sow more filler lettuce, to be planted out in the hoophouse during January. Transplant the first “filler lettuce” to replace casualties. Harvest leaves from the transplanted lettuce.

December: Use the “filler lettuce #1” to replace casualties or fill other hoophouse space, for lettuce leaves in January and February, or heads in February. At the end of December, make a second sowing of baby lettuce mix, to harvest from late February to the end of March. Harvest leaves from the transplanted lettuce, and cut the first baby lettuce mix.

January: Use the “filler lettuce #2” to fill gaps in the lettuce beds up until January 25. After that is too late here for hoophouse lettuce planting, and we use spinach to fill all the gaps, regardless of the surrounding crop. Harvest leaves from the transplanted lettuce, and cut the first baby lettuce mix whenever it reaches the right size.

February: 2/1 sow the third baby lettuce mix, to provide up to three cuts, from mid-March to late April. In mid-February, consider a fourth sowing of baby lettuce mix, if outdoor conditions look likely to delay outdoor harvests. Harvest leaves from the transplanted lettuce, and cut the second baby lettuce mix when it sizes up. Harvest the first baby lettuce mix, clearing it at the end of February before it gets bitter.

March: Harvest leaves from the transplanted lettuce, and cut the second baby lettuce mix whenever it reaches size. Cut the third baby lettuce mix when it sizes up.

April: In the first half of the month, harvest the last of the transplanted lettuce as heads . Continue to cut the third baby lettuce mix until it gets bitter. Cut the fourth baby lettuce mix when it sizes up. Outdoor lettuce heads are usually ready for harvest mid-April. Plan to have enough hoophouse harvests until the outdoor harvests can take over.

Lettuce transplants in soil blocks, on our custom-made cart. We don’t use soil blocks for lettuce any more (too time-consuming!) but I love this photo. Photo Pam Dawling


The February issue of Growing for Market is out, including my article How to decide which crops to grow which I previewed some of here last August. I also included some of the material in my slideshow Diversify Your Vegetable Crops. Click the link to see the slideshow. This past winter we used this kind of process to reduce the amount of garden work for 2017. I’m retiring from garden management and the new managers  want to stay sane and not be exhausted all the time. We have fewer workers this year (the past few years actually), so we needed to slim down the garden and not go crazy trying to do everything we’ve done in the past. I’ll still be working in the hoophouse, the greenhouse, and doing some outdoor work, as well as being available to answer questions and provide some training when asked.

Back to Growing for Market. There’s a great article for new small-scale growers, from Katherine Cresswell in northern Idaho, Year One Decision Making, about starting a farm with only one implement. Careful planning lead Katherine and her partner Spencer to focus on fall, winter and spring vegetables, as no-one else around them provided these, and they had experience of winter growing from working on other farms. Clearly a high tunnel (hoophouse) needed to be in the plan. It was essential that they hit the ground running and have saleable produce within six months. The expense budget was very tight. They bought a BCS 739 walk-behind tractor (which they both had experience of) and a rotary plow. A very down-to-earth article to encourage any new grower with limited means.

There are reviews of three new books by GfM writers: Compact Farms by Josh Volk, Floret Farm’s Cut Flower Garden and The Greenhouse and Hoophouse Growers Handbook by Andrew Mefferd, the editor of GfM. Brett Grohsgal has written a valuable article about his 15 years experience with on-farm breeding of winter-hardy vegetables, both in the field and under protection of hoophouses. Informative and inspiring. Erin Benzakein has written about rudbeckias, the unsung heroes of summer bouquets, and Gretel Adams has written on new flower varieties to try in 2017.


I have a new post on the Mother Earth News Organic Gardening blog, Using Open Flats (Seed Trays) to Grow Sturdy Seedlings Easily – How to make reusable wood flats (seed trays) for seedlings, and use them to grow sturdy vegetable starts to transplant into your garden. This is a way to avoid contributing to the problem of agricultural plastic trash and be self-reliant in gardening equipment. You can also grow stronger plants by giving them a larger compost volume than plug flats or cell packs provide.

Open flat of broccoli seedlings.
Photo Wren Vile

I heard that my MEN blogpost Green Potato Myths and 10 Steps to Safe Potato Eating was very popular in January, coming sixth in their table of most-viewed posts on all topics. This has been out there in the blog-iverse for almost 18 months, so clearly there is a lot of concern about eating healthy food and not wasting what we’ve grown.

Sorting potatoes two weeks after harvest to remove problem potatoes before rot spreads.
Photo Wren Vile


The false spring has been barreling along. Last week I reported that we’ve seen a flowering crocus (2/17). Since then, we’ve seen daffodils and dandelions flowering, heard spring peppers and already the maple is flowering (2/25). These are all markers on our phenology list. The maple flowers on average 3/12, with a range (before this year) of 2/28 in 2012 to 4/2 in 2014. A 9-year record broken!

Hoophouse winter greens, transplanting spinach, crocus flowering

Russian kale, yukina Savoy and lettuce from our winter hoophouse .
Photo Wren Vile

Our hoophouse is bursting with winter greens. We just decided to hold back on harvesting our outdoor Vates kale and focus on the greens  which are starting to bolt in the hoophouse. That includes the last turnips (Hakurei, Red Round and White Egg), Senposai, tatsoi, Yukina Savoy, mizuna, Ruby Streaks, Scarlet Frill and Golden Frills mustards. Big but happily not yet bolting are the spinach, Rainbow chard and Russian kales. A row of snap peas has emerged. Time to stake and string-weave them!

The lettuce situation is changing as we are eating up more of the overwintered leaf lettuce in the hoophouse. The lettuces in the greenhouse have all gone, to make way for the flats of seedlings. Plus, we needed the compost they were growing in, to fill the flats. More about lettuce in February next week.

We have also cleared the overwintered spinach in one of our coldframes, so we can deal with the voles and get them to relocate before we put flats of vulnerable seedlings out there. The voles eat the spinach plants from below, starting with the roots. We had one terrible spring when they moved on to eat the baby seedlings when we put those out there. After trial and error a couple of years ago, we now clear all the spinach from one frame, then line the cold frame with landscape fabric (going up the walls a way too), wait two weeks, then put the seedlings out on top of the landscape fabric. The voles by then have decided nothing tasty is going to appear there, so they move on.

Spinach over-wintered in our cold frame
Photo Wren Vile

Outdoors, we have just started transplanting new spinach. We have four beds to plant, a total of  3600 plants, so we have to keep moving on that! We are trialing several varieties again, as we did in the fall. We have the last Tyee, alongside Reflect and Avon this spring. Inevitably things are not going perfectly according to plan. Yesterday I forgot to follow the plan, and we started with Avon and Tyee at opposite ends of a bed we had planned to grow Reflect in! Anyway, we are labeling everything and hoping to learn which have best bolt resistance. Watch this space.

We have grown our spinach transplants (as well as kale and collards) in the soil in our hoophouse, sowing them in late January. I wrote about bare root transplants in early January this year. You can find more links and info in that post. Growing bare root transplants saves a lot of work and a lot of greenhouse space.

For those relatively new to this blog but living in a similar climate zone, I want to point you to The Complete Twin Oaks Garden Task List Month-by-Month. It includes a link for each month’s task list. I notice from the site stats that some of you are finding your way there, but now there are so many years’ worth of posts it’s perhaps harder to find. Happy browsing!

Following on from last week’s mention of harbinger weeds of spring: chickweed, hen-bit and dead-nettle, I can now report that I’ve seen a flowering crocus (2/17), another marker on our phenology list. The average date for first crocuses here is February 8, so they are later than usual. I did notice however, that the foot traffic over the patch of grass has been heavier than usual.

Anne Morrow Donley sent me a link to WunderBlog®, the blog from Wunderground, my favorite weather forecast station, to an article by Bob Henson: This is February? 80°F in Denver, 99° in Oklahoma, 66° in Iceland, 116° in Australia. It includes a map of the Daily Spring Index Leaf Anomaly, Figure 1.

Image credit: USA National Phenology Network via @TheresaCrimmins.

Figure 1. An index of the seasonal progress of leafy plants shows conditions 20 days or more ahead of schedule over large parts of the South and Southwest as of Sunday, February 12. Image credit: USA National Phenology Network via @TheresaCrimmins.

The post has lots of other interesting weather info too. Thanks Anne!


I remembered another of the items lost in the hacked post a few weeks ago: My Mother Earth News Organic Gardening Blogpost on Heat Tolerant Eggplant Varieties made it into their 30 Most Viewed blogposts for 2016. I’ll be writing up more about those varieties, linking the 2016 results to the weather each week (especially the temperatures) and adding what I learn in 2017.