Spurred by a question in a farming group on Facebook asking about end walls that allow tractor access I thought I’d outline a few of my preferences, and tradeoffs with different designs. Over the years I’ve seen a lot of hoop house and greenhouse end walls and I’ve built quite a few as well. The photo above is the most recent design I’ve used. It’s my most recent iteration of a longstanding roll up end wall and was inspired by some of the designs below. It’s relatively cheap and easy to build and use, and it allows full access to the house with a tractor.
Here in the Northwest we’re not worried about extreme low temps so the vent at the top of the end wall isn’t designed to seal super tight, but it activates automatically with a wax cylinder opener and is very, very good at keeping the tunnel from overheating in the early spring when we go back and forth between sun and clouds all day long and we don’t want to leave the ends rolled up. The “hinge” is just two bolts on either side of the frame.
The posts on the outside of the rollups are important to keep the door from swinging dangerously in the wind. Most of the winter the sides of the door plastic are just wiggle-wired to the full frame. The wire comes off when we start rolling up the door. To access the house there is a small door framed in the side wall (barely visible on the far side of the house). Yes, the door is only as tall as the vertical part of the wall so you have to duck to get in unless you’re really short. The side walls are also roll up, but the one on the far side only rolls up to the door, stopping a bit short of the end of the wall. This little access door saves a lot of wear and tear on the roll up, and makes access much easier when the end wall is rolled down. I think the biggest problem so far with this design is that the little wooden “roof” from the supports is a perfect place for yellow jackets to hang their nests. The one other slightly tricky bit is that you have to roll up the doors before rolling up the sides. Not really a big deal as that’s the way it usually works anyway.
The tunnel above is a 20’ wide low profile semi quonset type from Oregon Valley Greenhouse and is at Our Table Farm in Sherwood, OR. Below is a 30’ wide tunnel at Liberty Gardens in Pennsylvania. The roll up doesn’t quite extend to the corners of the house, but there’s still pretty good access.
Not shown in the photo is a center post that they use to keep the door from swinging in the wind. For a 20’ opening in moderate winds I haven’t found it necessary, but I think it probably is essential for a 30’ opening. There is a piece of pipe driven into the ground that the support pipe slips down into and then it’s attached to the top of the door frame when they’re not actually using the tractor in the tunnel (or at least that’s my memory of how it worked). Doors like this are big sails, and with a little wind they can exert a lot of force on the supports so it pays to really secure them well. This can be really tricky in wet soil. I’ve had a lot of stakes I thought were secure wiggle their way out of the saturated soil over night with gusty winds.
Here’s another version of a roll up end wall on a Haygrove single bay 3 season tunnel up on Foxglove Farm, on Salt Spring Island in BC. I put up this photo because this one uses extra heavy plastic on the door to reduce the effect of wear. It also uses their quick release clips with vinyl tape to secure the plastic, which is actually pretty secure, and does come apart easily (the tunnels are designed to be moved seasonally).
For their more permanent tunnels at Foxglove, Michael framed very light end walls that attach with a few bolts. The end walls have a light door in them, but when he wants to access the insides of the tunnels with the tractor the bolts are removed and two people can carry the end walls off to the side and lay them in the grass (this happens about twice a year).
Another design that I’ve seen in a few places, and tried myself, is scissoring doors. I first tried these with some multi-bay Haygrove tunnels. It’s a cheap, “easy” design, but there are enough problems with it that I gave up. The primary trick is how to secure the doors from swinging into and out of the tunnel. Usually these doors have a piece of pipe that hangs from the center top of the end wall and can be tied up to the side wall when you want to open the door. The pipe needs to be secured at the ground when the door is closed, and sandbags were not nearly enough in our case, nor was a steel contractors stake driven 2’ into the ground, or a light T post that the doors broke after a few weeks of the wind tugging on it. Tying ropes horizontally across the end bows about 3’ off the ground, both inside and outside the door did help, but we had to untie them any time the tractor was going into the hoop house. We gave up on the pipe and just used them as curtains for a little while (shown in the photo from Sauvie Island Organics, near Portland, OR circa 2006), but eventually we gave up on the end walls all together for these three season tunnels and just used the tunnels as giant umbrellas, which is what we needed most anyway.
When I visited Eliot Coleman in Maine in 2015 he was working with scissoring doors on his tunnels. I don’t remember the details of why, probably mostly for good air flow with something that was easy to access. His tunnels have a bar that runs across the opening so no good for tractor access (but he does the tractor work before moving the tunnel over the crop), but a perfect place to secure the scissoring pipes. At the time he was just using a bolt with a wing nut and had holes drilled in each of the pipes. It was a slick design, very simple and effective for his needs.
I get questions from readers every once in a while and I keep a long file of ones that I think would be good to write about. Unfortunately I mostly don’t get around to answering, but I thought I’d take a stab at this one (from two years ago, yikes). I appreciate hearing that folks are actually reading what I have to say and that they’re getting something out of it, and it’s always amazing to me that the internet means my opinions are available in pretty much any corner of the globe.
I’m wondering if you’re interested in writing an article about what to do when things do not go according to plan. I’ve been thinking it’s the one topic that nobody covers, but in farming there are so many things we can’t control. I’m thinking – too muddy to hoe, storm kills seedlings etc. Be interested to hear your process for decision making in difficult times. Anyway, thanks for all you share, Esther Pickle Creek Farm Sydney, Australia
(note- This was so long ago that Esther isn’t actually at Pickle Creek Farm any more, but she did come visit on a tour of US farms last summer so I got to meet her in person as she helped us tie up young tomatoes.)
My quick reply to Esther at the time was that I don’t think there’s actually a straightforward answer to how to make decisions on the farm in difficult times and perhaps because it’s so complicated folks don’t write about it much. I’ll think out loud here a bit and maybe some part of my thoughts will help one of you out there reading this.
I’m a planner, I plan out my farm seasons week by week a full year in advance. Notice that I write “week by week” and not “day by day”, or “hour by hour.” It’s good to have a plan, for me it’s indispensable, but I come into the season realizing that the plan doesn’t include every detail, and that it has to be flexible. On the farm my weeks have usual flows, meaning harvests happen on certain days at certain times, creating weekly to do lists and records usually happen on certain days, plantings and cultivations have typical times that they happen.
Following the plan made at the beginning of the year everything is further prioritized on the actual week it’s planned for and is continuously reprioritized as more information comes in on actual field conditions – if only in my head. There’s a lot of strategizing and observation constantly happening as I’m working. Market times, whether that’s CSA pick up, a Farmers Market, or a restaurant order delivery, are usually pretty set and don’t have much flexibility, but even those can change when things get extreme if needed and that’s good to keep in mind. Harvest sets up successful markets so that tends to be the next priority for me. Good cultivation, irrigation and field maintenance sets up good harvests so that is usually my next priority.
Planting usually comes after all of those and if I miss a planting it’s a problem so I try not to do it. I work hard to set myself up so that everything else gets done so I can plant. In terms of prioritizing, I’m usually focused on the crops that will take the least amount of labor and expense going forward to get to market. To belabor the point, I’m not thinking about the sunk cost here, the amount of time and expense that already went into a crop, I’m thinking about the amount of expense remaining and potential returns when prioritizing. Within plantings I almost always prioritize plantings of crops that have successions to keep the succession of harvest as even as possible. For one time planted crops I’m more likely to put off plantings if other things need attention and assuming the weather looks cooperative and any seedlings look like they’ll survive.
To go back to that point about sunk costs one more time, always move forward, you can use the past to inform your decisions, but you can’t go back and change the past. In decision making about a current crop, the future expenses and potential returns are all that matters, not what it has taken you to get to whatever point you’re at. Look at costs and returns in a wholistic way, take into account how much extra weeding will be involved with saving a crop and if the potential harvest will pay for it; if you’re four weeks late planting beans, will you have the labor available four weeks after you originally planned on harvesting them; if you need to work up a field that just won’t dry out what will that do to the soil texture for the next year, or five?
When things go wrong, like it rains for a week straight, or two, it means something that needs to happen isn’t going to, or at least it’s not going to happen at an ideal time or in ideal conditions. Part of the calculus is thinking about the consequences of not doing each one tasks involved and how those consequences will propagate out over the rest of the season, and even in future seasons. In the simplest terms, it’s then just a matter of giving up on whatever task is going to cause the least impact into the future.
The only way I can think to make a general statement on how those decisions get made in a timely manner is to say “with experience.” Experience helps in multiple ways and there is no substitute. The more experience you have as a farmer the more likely it is that you’ve seen some variation of this same problem in the past and so you have at least one experience of how it plays out. The more experience you have the more practice you have prioritizing and the less time it takes to prioritize effectively.
One way to practice more, and build up a certain kind of “experience” more quickly than just waiting for season after season to pass is to study farming: read farming journals and books, visit farms, talk to other farmers, go to conferences and hear what other folks are doing, and especially what has worked in the past, under what conditions and why. Another way is to plan, and while you’re planning keep in mind contingencies. Every good plan is made with realistic conditions in mind. If you’re planning on planting into a field the second week of April, how likely is it that that field will actually be ready the second week of April and that the weather will cooperate? What are the consequences if it’s not ready, what are the alternatives. These are all things you can think about in advance and winter, for most of us, is a perfect time to spend time thinking about these things – practicing farming, practicing decision making and prioritizing, stocking up on options and contingencies before we actually need them.
If the plan is “perfect” it has enough built in contingencies that all of the decision about what to do are already addressed. No plan is perfect. Plans that acknowledge the limits of planning are much better than ones that don’t though – that’s why in the winter I only plan out plantings by the week, not by the day. I know I’m not really going to know what day is going to be the best to plant six months in advance, but I can get the week right most of the time, and then decide on the actual day when the time comes closer. To continue using planting as an example, I also know the steps for setting up a successful planting and so I’m proactive in watching the weather, watching the soil, moisture, and flora to make small adjustments as the time for planting gets closer. I’m willing to compromise on being “perfect” and accept what I think is merely acceptable when that’s the best I can do.
For me, planning and strategizing is happening continuously on different levels. It’s paired with, and informed by careful observation of and record keeping on what actually happens, and that includes not just the pieces I have some control over, like when a seed is seeded in the greenhouse, but also the natural surroundings that I have no control over and their patterns and lack of patterns over time.
In January I somehow came across a Facebook post from Steve House, a well known Alpinist and Patagonia climbing ambassador.
I have to admit I was nervous about mentoring young, technically capable climbers and alpinists when I started in 2012. What could I teach them if they already know how to swing an axe, cross a glacier, and rig a rappel?
I learned that experience in the mountains is a way of seeing. A way of knowing. And gaining that experience is painstakingly slow UNLESS someone shares their intuition, their judgement with you.
A seasoned climber looks at a route, and sees solutions, options, obstacles, present dangers and so much more. The novice looks at the same mountain and sees the route itself, but maybe little more.
Perfect, and it came at a time when I was questioning my value as a consultant and a mentor.
January and February brought back to back to back events putting me on both sides of this equation. One of my long time mentors has been Michael Ableman, and in January he invited me to participate as one of the younger farmers in the second version of a meeting of Agrarian Elders. The initial event in 2014 was a discussion between elders of the organic farming movement, farmers who have been pushing the movement forward for forty or more years. At the second version roughly half the elders returned, bringing a younger farmer each, and I was fortunate enough to be one of those who had the opportunity to literally sit at the feet of the elders and listen for a week.
The following week I returned to Portland and was invited to talk to an introductory design class at Portland State University that a friend of mine was teaching. She promptly introduced me as one of her mentors and a leader in the local farming community, something I wasn’t expecting at all, but made sense in the context as I was at least 20 years older than everyone in that class, and a few years older than my friend, who I’ve known for more than a decade now. It was a surreal reversal.
The next week I headed down to Breitenbush Hot Springs for an annual retreat with farmer friends from around the Northwest. Spring training camp for farmers as Robelee Evans, farmer, baseball fanatic, and one of the organizers and instigators behind the event described it. I’ve been a part of that group for 13 years, one year shy of the start. Partially because I was one of the youngest farmers when I started coming, and I didn’t start coming until the second year, I’ve always kind of though of myself as one of the younger, newer farmers in the bunch. This year I had the strong realization that my role there is changing, and I’m now a bit more solidly in the middle, with many farmers I look up to still there, but also many farmers who are relative novices.
I’m starting to embrace my status as a more seasoned farmer, but I still have many mentors with many more seasons under their belts and I listen intently to their intuitions and judgements and I try to understand them in the context of what I’m seeing and experiencing myself on the farm, and in my life.
I’ll try to make time to post a little more regularly this year, perhaps monthly, perhaps a bit more. I’m also working on setting up sites to offer a little more insight into the gatherings at Esalen and Breitenbush. The topics discussed there and resources shared are important and I think we all want to make them more accessible to the larger public.
I can’t remember when I first came across Allen Dong’s hand drawn directions for converting a chipper shredder into a bean thresher, but it was a long time ago. He has shared a large number of other designs over the years for small scale, DIY farm tools. His designs look, and are, straightforward to build, with mostly common, inexpensive or salvageable parts and without the need for overly special tools. The designs are very well thought out to serve their purpose, something that is not completely obvious without looking at the details and in some cases seeing Allen demonstrate the simplicity with which they work.
I felt very lucky to be at the OSU Small Scale Equipment Field Day last month where Allen was demonstrating his bean thresher, several winnowers and a hand operated screen, and a vacuum packer for storing seed. I took a few photos and I’ve put a link to them up on the photos page. Make sure to click on the thumbnails to get larger versions.
Monday night was the Culinary Breeding Network‘s 2nd Annual Variety Showcase in Portland, Oregon. The event brings together seed breeders working on varieties for organic production, farmers, and chefs to highlight the work that they are all doing to promote new and special vegetable varieties. Lane Selman, the organizer and force behind the Culinary Breeding Network, does an incredible job of bringing seed breeders from all over the country, and pairing them with chefs who can prepare their vegetables into tastings that give a sense of their potential.
The format for the event is pretty simple: seed breeders and/or farmers are paired up with chefs well in advance and the chefs work with the vegetables to prepare a tasting. On the night of the event tables are set up around the perimeter of the very lovely cafeteria at Chris King Components (a high end bicycle parts manufacturer in Portland that has a love of good food). The tables are set with displays of the vegetables, dishes with raw samples, and the samples that the chefs have prepared. The room filled with journalists, chefs, farmers, and seed breeders and then Lane made some opening remarks giving the context and making short introductions to the participating breeders. After that it was just a big crowd of about 200, sampling the goods and talking with the chefs, breeders and farmers, and each other about what they were tasting. Lane also put together excellent print materials to help guide people through the event and the tastings.
As a farmer, I’ve been working with Lane on vegetable projects for about ten years now and she’s always included tastings in the work that she’s involved with, not forgetting the importance of flavor when we’re choosing varieties. We’ve worked together, and with lots of other farmers over the years on countless crops, mostly trailing varieties under organic production methods to look at their potential for yields, disease resistance, storage, cold tolerance, etc., but always also looking at flavor. In all of these trials we’ve looked at commercially available varieties, but from the very beginning we’ve also been trailing new plant material from seed breeders along side the commercially available seeds. About seven years ago she started inviting chefs to be a part of the conversation and the synergy is incredible.
Now, at the Variety Showcase, we have all three groups in the same room at the same time. As a farmer I’m able to talk to the breeders about what characteristics I’m looking for, and to the chefs about what they’re looking for. They are also giving me ideas about new crops, new techniques, new marketing avenues, and I get to see, touch, smell and taste the products right there. I had a great time catching up with friends from the food world and getting inspired by new crops and incredible preparations of old crops that give me new ideas.
I was tabling with Andrew Mace from Le Pigeon and Shaina Bronstein from Vitalis Organic Seeds. With Our Table Cooperative I’ve been growing fennel trials so we had 6 to sample at the table, and Andrew had made a take on chips and dip with the fennel that was delicious. I didn’t have a chance to make it around to all of the other tables; every time I’d go out to try to see what was out there I’d run into someone I wanted to talk to and then spend all of my time on just one or two items, but I did get to see most of it, and I talked to a lot of people about fennel and what I’ve noticed growing a dozen different varieties side by side this year. In the mix of crops being highlighted were carrot breeding lines, sweet corns, or perhaps more accurately vegetal corns which are sweet but also have amazing corn flavor and are for fresh harvest, really exciting work on American groundnut (Apios), winter squash, many different peppers and beans, winter melon, barley, wheat, shiso, parsley, and probably a hand full of others I either missed or didn’t get a chance to see.
This event in some ways is showing food at an exclusive craft level, but in typical Oregon style, it is anything but elitist. The emphasis is on featuring the vegetables, the importance of moving our food system forward, towards Organic techniques, and celebrating the breeders who are making this possible while raising everyone’s level of understanding and creating positive connections.
I made some long overdue updates to the Farm Hand Carts website today. Building the hand carts and working on improvements and accessories is a project that is currently stalled, but that I’m hoping to get back to soon. The updates to the site include adding a few more recent photos, photos and links to other folks carts, and putting a little sign up for a newsletter that will let folks know when things really get back up and running.
This blog is also long overdue for some posts. I’ll see if I can’t remedy that in the near future.
I’ve gotten a lot of questions about my drip winder recently. Way back in November 2009 I wrote an article in Growing for Market on the winder, how to build one and how to use it. I have a lot of old articles in Growing For Market’s archives on similar topics. I’ve updated that one with a slightly different design on my website here. I highly recommend getting access to the Growing for Market archives by signing up for full access and checking out some of the old articles there, and I don’t just mean mine. You could go back and see what changes I made to the drip winder if you like, but you can also find tons of great articles by growers all around the country.
Tanya Murray, Organic Education Specialist at Oregon Tilth, has created a great program with small vegetable farms around Oregon to help them to start looking at the costs of production for crops they are growing. This project is a collaboration between Oregon Tilth and the OSU Small Farms Program which is working towards long term viability of small farms.
I’m participating, collecting numbers from Our Table Cooperative to help us better understand our labor needs, expenses and to look for places where we can improve our systems to lower our costs. As a participant I’m sharing those numbers with the other farms in the program, but more importantly we’re all sharing our methods for collecting the numbers effectively through a listserv for the participants.
Tanya is coaching us through the process and every three weeks we switch to a new area of the farm to focus on, kicked off by a webinar where Tanya presents the numbers that need to be collected and formats for collecting the information. A few weeks ago we came to the end of the three week section on greenhouses and producing seedlings. I have some initial numbers that I’m still inputing, but I also built on the Excel workbook that Tanya created for an afternoon workshop on the same topic that she and Ellen Polishuk presented at the Oregon Small Farms Conference in March. Here’s a link to an Excel version of that workbook.
This workbook is a work in progress and I’ve populated it with some example numbers. They’re not super accurate, but they’re in the ball park and should help demonstrate how the file works. This is a workbook I set up for myself so it’s not completely “plug and play”, there’s some need for anyone using the workbook to understand Excel and it’s helpful if you understand how to write basic Excel formulas (addition, multiplication and that sort of thing). Here are some of the features of the workbook to get you started.
There are three sheets in the book: Overhead Costs, Filled Tray Costs and Crop Costs. Overhead costs lists out the basic costs of the greenhouse structure, furniture and utilities. These are costs not really tied to any one crop, and that don’t change directly in relation to the number of trays that are in the greenhouse. At the top of that sheet there is a number titled “est. total tray weeks.” That number comes from adding up the number of trays that are in the greenhouse every week. For example, if there are 10 trays on the first week of April and 20 trays on the second week that’s a total of 30 tray weeks, regardless of whether some of the trays are the same tray or not. I use this number to divide the “overhead” costs and get a cost per tray week. This makes trays that are in the greenhouse for longer significantly more expensive as overhead ends up being the biggest expense for me in producing seedlings. You could decide to allocate the overhead differently if you had a different way you thought was more fair, and if you do have a way I’d be interested in hearing about it. I got my total tray weeks estimate from the crop planning that I do, which is explained here. It makes it relatively easy to write a simple formula to add up all of the tray weeks planned for in a year.
One thing you should recognize here is that once you have invested in a greehouse, the more you can maximize its use the lower the cost per plant. We’re far from maxed out on using our greenhouse space and we could probably cut the overhead cost in half if we had a way to double the number of trays we produced in a year. We’d also have to have a way to use, or sell those extra trays, but it would bring the cost per plant down significantly for some of the starts.
You’ll notice through the sheets that no cells are locked so you can put whatever you like into any of the cells. Some of the cells have a background gray color; those are cells with formulas that are intended to be kept for standard calculations. The white cells are intended for inputting numbers. In some of those white cells you’ll notice formulas, but these are simple calculations when I have the number in one set of units and I need to convert.
The second sheet is “Filled Tray Costs.” This sheet looks at the cost of different size plug trays that we use, and what it costs to get them ready to “seed.” I put “seed” in quotes because preparing one of these trays for seeding is the same as preparing it for potting up, but it’s all called “seeding.” There are a couple of slightly hidden things I think I should point out about this sheet. One is that the labor rate that this sheet uses is actually on the next sheet, “Crop Costs.” Another is that there’s a relatively fancy “if statement” in the “Crop Costs” sheet that references the cell tray sizes I use. If you change any of these cell tray sizes (which is a likely thing if you use different size cell trays from me) you’ll need to update this “if statement” if you want the “Crop Costs” sheet to work for the new cell tray sizes.
The last sheet is the “Crop Costs” sheet and this is where you get the exciting final numbers. I’ve put the final calculations in three forms: per plant used, per tray, per bed. The per plant used takes into account that not all of the cells of a plug tray will germinate, and not all of the cells that germinate will be planted out. This number makes it easy for us to calculate reasonable sales prices for selling starts to home gardeners and also makes an interesting quick way of looking at the price of something like a head of lettuce where we’re selling the final product one plant at a time. The per tray costs is just what it says and I have that there because we may sell trays in the future, but also because it’s interesting to know if we were to seed an extra tray how much that costs us. The per bed cost is intended to be used for a future sheet which calculates out the total cost of producing specific crops.
To get to those final costs there are a bunch of intermediate numbers that are inserted to the right of those numbers and some calculations made. There are three numbers at the top of the sheet as well. At the top is the “loaded labor rate” which is the average cost per hour to the farm of an employee; the “minutes hand watering/tray/wk” which is zero in this case as I’m estimating these costs entirely on automatic watering; and “minutes/move” which is the time it takes to move a tray from one bench to another. For some crops we move the trays multiple times, adjusting their heat zone; others stay in one place until they are planted out.
One of the fascinating things about this sheet is looking at the relative expense of the different parts of the process of producing a seedling. The overhead is a big expense on the lettuce, but on the tomatoes it’s small and the seed is the big expense. Labor on seeding is relatively low, even though we’re doing it by hand. You’ll also notice that for the tomatoes, which are potted up, I split the cost into two parts: seeding the seeds and “seeding” the transplants, which you could also call potting up. For the second, I use the price of producing the seedlings in the place of the “seed” cost.
I’ll try to keep posting notes on the process of running enterprise budgets on the farm through the season. I’m very happy to see more folks doing this and sharing results. Some of the Universities, UC Davis in particular, have had enterprise budgets on their websites for a while now, but they’re usually formatted for larger production of single crops. Richard Wiswall has excellent examples of crop enterprise budgets on a diverse vegetable farm in the back of his “Organic Farmer’s Business Handbook.” I haven’t used it but Ellen Polishuk was touting the Veggie Compass tool which is available at http://www.veggiecompass.com and is more of a plug and play tool. Chris Blanchard has great interviews with both Richard and Ellen on his new Farmer to Farmer podcast, which is definitely worth checking out.
The other day I sat down with Louis at Our Table Coop to outline a cover cropping plan for the summer. For the past 15 years I’ve been using two basic cover crops here in the Northwest for filling in summer gaps in the field: buckwheat and sudan grass. I’ve experimented with a few others and I’m continuing to experiment, but those two are solid and each has a particular place. Creating the summer cover crop plan is pretty simple using those two crops, once the crop plan is mapped out, which I usually have done in December or Januay. The whole process of figuring out what beds would get buckwheat and which would get sudan, and how much of each we needed to order was done in about a half hour. Here’s are the basics of my approach.
Buckwheat gets planted anywhere there’s at least an eight week gap between crops starting in May. Sudan gets planted anywhere there’s more than a ten to twelve week gap starting in May. Gaps are easy to see on the map, they show up as white blocks and you just have to count the number of blocks between the last planned crop (or the expected maturity of a winter cover crop, usually mid-May to early June, and a late planted crop).
I have these kinds of gaps for several reasons and in other parts of the country they might not be as common. We’re typically cropping nearly all of our ground at least once, if not twice a year. Even then we can have blank gaps because our planting season is so long, starting in February and going until October in the field. Some of our cash crops are finished as soon as early April so there’s plenty of opportunity to build soil biology and organic matter and to keep nutrients cycling high in the soil profile by using cover crops in the summer.
A Few Details
Buckwheat takes between four and six weeks to start flowering and it starts setting seed shortly after it starts flowering, within a couple of weeks. The flowers are obvious and white so it’s kind of like a flag saying, “turn me in, now!” It goes faster with longer, warmer days and slower earlier and later. In either case it’s not going to last much longer than six weeks at the outside, and with four weeks, even if it isn’t flowering yet it will already have decent growth in most cases. I like to give a cover crop four weeks to break down before planting, therefore the minimum of an 8 week gap. If it’s less than 8 weeks, I’ll usually just let the weeds go for less picky crops, like tomatoes, or do a bare fallow for trash sensitive crops like carrots or salad greens.
That four to six weeks to flower is about as fast as any weed, but weeds aren’t as kind as the buckwheat and they don’t signal that they need to be mowed before they set seed in the same way. This is one of the reasons I like the buckwheat. Even if the patch is very weedy, those flowers give me a visual signal that I need to mow and incorporate or I’ll have seed setting, buckwheat and weeds.
I usually use a seeding rate of about 60-80 lbs per acre and I either broadcast it with a “belly grinder” (shoulder bag type broadcast spreader), or put it down with a drop spreader. It needs to be incorporated and a ring roller works well, or a shallow disking, or slowly dragging the rototiller over the bed with the pto off. I don’t worry about letting the previous crop break down much after incorporation before seeding, although it’s nice if it can be a week or two after the inital incorporation.
I’ve used all sorts of sudan grass and I’m not particular but I prefer the smaller stemmed types like Piper. In the past it’s been important to specify untreated seed as the seed is commonly treated with fungicide, at least in our area. I have an impossible time finding Organic buckwheat or sudan seed, which makes me think I should start growing it myself. Immediately after that thought I start thinking there must be some reason no one is growing it organically for seed on a small scale and that I’d probably find out why if I tried to.
The sudan starts out a little more slowly than the buckwheat, but it can be maintained essentially indefinitely with mowing, at least until first frost when it will die. I use the same seeding technique as with buckwheat, and go a little heavier, maybe 80-100 lbs per acre. It varies quite a bit how long it takes, but whenever the suday starts to elongate, as if it’s about to send up seed heads, I mow it short. This is usually timed pretty well to knock back any weeds starting to set seed as well. It’s possible to keep mowing it weekly and to maintain a sod, I’ve done it to create alleys in summer squash and melon plantings, mowing regularly with a flail mower, but if I’m just using it as a cover crop I’ll let it go until it is about to head out again before mowing it a second time.
Even though we don’t get any rain in the summer I only ever irrigate these cover crops once, giving them a little over an inch immediately after seeding. There is no question I’d get more biomass if I irrigated more. Whenever the crop is on the edge of a sprinkler irrigated crop and it gets over spray it gets significantly larger. To me, it’s not worth the extra work, or the extra electricity and displacement of limited water resources to get the extra biomass, and I still get good growth and coverage. I do water again after incorporation (or just before if it’s too dry to work in, which is usually not the case as the plants seem to keep the water pumped up into the upper levels of the soil). I water after incorporation to help it break down and to germinate any weed seed that is near the surface during the four week wait before planting a cash crop.
How to Complicate Matters
I really like grass/legume mixes, as the grass and legume are complementary. The grass is good at taking up soil nitrogen, which encourages the legume to work with rizobacteria to fix more nitrogen from the air. The two nurse each other, and the upright structure of the grass provides a scaffold that helps any legume to climb and make more bio-mass without shading itself out.
The legume I’ve had the most success with in Sudan is clover. There are two ways I plant clover with sudan. I have had some success seeding it at the same time as the sudan, although I usually do this in separate passes since the seed sizes are so different it’s hard to mix evenly, and they don’t throw the same distance from a broadcast spreader. This works ok, but the sudan tends to outcompete the young clover, which isn’t well suited to the hotter, drier time of year. The other way I seed it is to wait until a mowing in September and then to broadcast the clover seed over the mowed sudan. It usually starts raining soon after this and the clover comes up sheltered by the sudan, and then takes over in the winter when the sudan dies back, providing more growth and cover through the winter.
There are two clovers I use: crimson and red. I use crimson if the field is going to be turned in in the early spring, especially if the next crop is sensitive to trash. Crimson clover is easier to kill than red clover, and this works especially well because the sudan is mostly broken down by the late winter and the lush clover works in easily.
I use red clover if the field won’t be planted until later the next summer, or even fall, as the red clover is a weak perennial and is deep rooted enough that it can be mowed at flower and continue through the following summer with no supplemental irrigation if needed.
For a while now I’ve been wanting to try sunflowers as a summer cover crop alternative to sudan. Mostly I just think this would be a pretty alternative, but I also hear that sunflowers can create significant biomass.
I somewhat consider my plantings of dry farmed popcorn, flint corn, dry beans and winter squash as a summer cover crop. They are very low input since they’re not irrigated, and low yielding, but they give an excuse to keep the field clean and they provide cover all summer. There is significant biomass above what is harvested. I haven’t done it yet, but every year I think I need to spin on some clover when the squash starts to die back to provide more winter cover. I have friends who do this before the canopy fills in in early summer, but they’re irrigating with sprinklers so it’s a very different situation for them. We finish harvesting the field too late to get it worked up for our typical rye/vetch winter cover crop, or at least it always feels that way.
A lot of folks talk about the wonders of mustards and forage radishes as cover crops, and for orchard or grain situations I can understand that. For vegetable production, particularly in a place where brassicas are so important as a cash crop and club root is such a big problem when rotation are short, I can’t see incorporating a brassica as a summer cover crop. Although, similar to the corn, beans and squash, I do think of high density salad greens, which are largely brassicas, as a great cover crop. I frequently let these go to flower before turning them in, which probably doesn’t help with club root problems, but it does provide beneficial habitat and is essentially a free cover crop since it’s already planted and it will still grow thickly after harvesting.
Things I’ve Tried
I’ve tried a few other legumes. Cowpeas never did well for me and I think we’re just too cold for them. I did have a good crop of soybeans one summer, using old edamame seed, but someone told me they’re hard on the ground, and the seed isn’t cheap so I abandoned the thought in subsequent summers.
As much as I like the idea of super diverse cover crop mixes, the simplicity of the variations I have now means they actually get planted and are easy to manage. I think that’s a good starting point for anyone new to cover cropping and it’s way better than the alternative, which is bare, or weedy ground.
I just made an update to the page on making Wooden CSA Boxes. This includes an update to the lid design which makes them a little cheaper and easier to assemble, and should make them much stronger and more functional. I walked Louis (whose hands are featured above) through the full process of building the boxes and I was really glad I had my old post to remind me how I did it the first time. After two years we’re building 63 more of these boxes and we’re finding more uses for them around the retail end of the farm.