Concerning the Bio-Extensive Market Garden
by Anne and Eric Nordell of Trout Run, PA
A Diversity of Cropping Systems
As a matter of convenience, we plant all of our field vegetables in widely spaced single rows so we can cultivate the crops with one setup on the riding cultivator. Widely spaced rows also provide each plant with a large reservoir of moisture and fertility, enhance air circulation, and make it much easier to cultivate delicate vegetables in stoney or high residue conditions. Row cropping makes sense for us because we are more limited by labor than land and we don’t use irrigation for the field vegetables.
The comments from several visitors made us wonder if our wide row example has given perspective teamsters the impression that all horse-powered market gardeners row crop their produce and consequently earn much less per acre than multiple row tractor farmers. The reality is teamsters use a wide diversity of cropping systems as documented in Stephen Leslie’s essential books, The New Horse-Powered Farm and Horse-Powered Farming in the 21st Century. As for the economics of planting produce in work horse friendly single rows, revenue is comparable to many multiple row tractor systems.
The chart for our Beech Grove Farm itemizes the sales for all the crops we grew last year. For comparison purposes, we extrapolated the return per 380’ row to an acre basis, fully realizing that these numbers may be suspect due to a whole host of variables that can change when scaling up production, such as prices or insect and disease pressure. The extrapolated return per acre for many of our dry land vegetables is within the range of enterprise budgets for multiple row tractor operations we have seen as is our average return per acre of $19,500 for the 3.2 acres in field production in 2015.
The crop yield and revenue spreadsheet for David Fisher and Anna Maclay’s Natural Roots CSA in Conway, MA makes a much stronger case for row cropping with horses. Using different management techniques, including narrower row spacing and packing more plants into each row, their extrapolated returns are, in some cases, two to three times ours.
Anna and David’s total vegetable income in 2015 was $97,036 for 3 1/2 irrigated acres in production or almost $27,500/acre. Since most of their vegetable revenue comes from CSA shares, they based the prices for their per acre extrapolation on their local food coop’s prices minus 25-33% due to differences in overhead costs, location, customer convenience and produce selection.
Other important details on putting together these spreadsheets: To determine the income per row foot, both farms counted all the area planted to each crop regardless of whether the entire crop was harvested or marketed. These calculations also took into account adjacent rows needed to grow the crop to maturity even if these adjacent beds were planted to another crop. For example, David and Anna typically alternate rows of sprawling cucurbits or trellised nightshades with short term vegetables. We do the same during the establishment year of strawberries alternating rows with lettuce.
Although 2015 was a good year for both farms, not every crop performed as usual. Phytophthora, a new disease at Natural Roots, ended the season prematurely for some of David and Anna’s cucurbit and solanaceous crops. The yield of winter squash, potatoes and one variety of garlic was well below average on our farm and demand for salad mix and spinach at the growers market was lower than in recent years.
Anna and David organized their chart by extrapolated revenue per acre so readers could quickly see which crops had the highest potential return. We listed our vegetables in order of total income generated, reflecting our market niche. Both of these variables are needed to determine a profitable crop mix along with the cost of production, labor availability for harvest, and personal preference.
We were not successful in finding other horse-powered growers who kept crop yield or income records, but six experienced teamsters responded to our request to fill out the plant density chart for three transplanted crops. In several cases, plant populations equaled or exceeded standard tractor systems used here in the Northeast.
Tractor I is based on Richard Wiswall and Sally Colman’s Cate Farm in Plainfield, VT as portrayed in Richard’s Organic Farmer’s Business Handbook. We pieced together Tractor II from the enterprise budgets for brassicas and lettuce in Vern Grubinger’s Sustainable Vegetable Production and the onion plasticulture system used in Pennsylvania by both tractor and horse farmers. No doubt there are horse and tractor powered farms employing more intensive cropping systems than we captured in this plant density comparison.
We also learned that row spacing has changed in recent years for at least a couple of the participants in this survey. For example, Stephen Leslie and Kerry Gawalt of Cedar Mountain Farm in Hartland, VT have actually increased their row width from 32 to 36” in order to implement the horse drawn guidance system described in the Fall 2012 Small Farmer’s Journal. Despite the widely spaced rows, their planting density for broccoli is much higher than the tractor multiple row systems on the chart. When asked if there were negative consequences to planting brassicas just 12” apart, Stephen wrote back, “It is tight, but we seem to be feeding them what they want and it shades out weeds really well. Same with potatoes and same for lettuce at 9” in the row.”
All of the teamsters we contacted use multiple row plantings for some crops. At Natural Roots, David and Anna plant double rows of garlic, cilantro and edamame beans and triple rows of mesclun mix on their 32” beds. At Cedar Mountain and Beech Grove, many of the hoop house crops are planted in multiple rows.
Ken and Martha Laing of Orchard Hill Farm, St. Thomas, Ontario, grow lettuce, mesclun, dill, cilantro and green onions in multiple row beds on 72” centers because, Ken explained in his letter, “These crops are better suited to beds than rows – mostly space consideration, I suppose. They are easier to harvest because you do not have to move so much. We did grow head lettuce in rows but Martha thought I threw too much soil into the heads cultivating which was true.” The rest of the Laings’ vegetables are grown in 36” single rows and they grow $20,000/acre from their 7 acre CSA.
Martha and Ken save labor by using their carousel horse drawn transplanter to plant onions. The widely spaced single rows are easy to cultivate with their McCormick Deering riding cultivator. With 3 onions in a plug spaced 9” apart down the row, the Laings’ planting density is the highest of the horse powered operations and not far below the intensive Pennsylvania plasticulture system.
At Welcome Table Farm in Walla Walla, WA, Emily and Andy Asmus use a variety of row spacings. They grow most of their vegetables in single rows 36” apart; however, they spread the rows to 42” for corn and potatoes and 60” for tomatoes, squash and melons. Peas, green beans, carrots, beets and sunflowers go in double rows, 4-6” apart, on 36” centers, and lettuce, spinach, radish, Hakurei turnip, arugula and mizuna are direct seeded in 6-row beds, rows 6” apart, with 28” pathways. Before the soil warms up sufficiently in the spring for direct seeding lettuce, the Asmus’ transplant this crop in five-row beds on 52” centers, resulting in a phenomenal 101,000 plants per acre. Keep in mind that they use the majority of this intensively transplanted crop for cutting lettuce with select plants left to size up for harvesting as head lettuce.
As for cultivating the diversity of row spacings at Welcome Table, Emily explained in her correspondence that “we can straddle row cultivate single rows on either side of a block of beds, but use a walk behind cultivator for between such beds. For these short season crops planted 5-6 rows/bed, high density and reduced space in the field seems like a good exchange for less efficiency in weeding.”
Mac Mead, director of the Pfeiffer Center in Chestnut Ridge, NY, was the only teamster in this small survey to grow produce in raised beds. We asked him to explain the benefits for the horses, plants and soil:
“A semi-permanent raised bed system lends itself well to high productivity and to enhancing soil fertility. The enhanced life element of a raised soil is a perfect complement to a good lively compost. There is a very efficient use of compost when it is placed into the three foot wide planting top of the bed though the whole bed is five feet wide from path to path. Half of our one-and-a-half acre vegetable field rests in cover crops each year yet stays in raised beds. Compost is only applied to the production sections.”
“The beds have been laid out close to the contour lines using the Keyline concepts and many have been in place for years. The paths are firm allowing for good traction for draft sources be it animals or tractors. The actual beds remain quite soft and easy to work often only requiring “secondary” tillage and rarely “primary” tillage such as plowing. The width of our beds nicely accommodates handwork and nicely fit our Pioneer forecart with our horses spread wide and also fit our neighbors’ tractor if needed on rare occasions. I think it is good to have a flexible system that provides for optimum conditions for our crops and soil.”
The soil is so soft in the raised beds at the Pfeiffer Center, that Mac uses a small team of Halflingers to work in crops and cover crops with a five foot disc and three point hitch forecart. He adjusts the three point hitch so the back of the disc cuts in deeper than the front, maintaining the shape of the beds. Mac uses a toolbar on the forecart for marking 1, 2 or 3 rows for planting and for cultivating single rows crops on the beds such as potatoes and squash. He cultivates the pathways with a single horse and walk behind cultivator.
Due to Klaus and Leann Karbaumers’ flexible planting system and the fact that they direct seed most of their crops, we were not able to include Karbaumer Farm in the plant density chart. However, their Platte City, KS market garden is a prime example of how to grow a lot of produce in a limited area. Depending on the crop, its cultural requirements and its place in their tightly orchestrated succession plantings, the Karbaumers utilize single rows and double rows on 42” centers, single rows 20-21” apart, short term vegetables intercropped in the path- ways of longer term crops, and broadcast plantings serving as marketable cover crops. Klaus explained in one of his letters describing their complex system:
“Where I can, I cultivate with the horses, especially with our Halflinger, but I also use the wheel hoe, or various hoes. I do not like it if a tool forces me to a special way of using the available area. I am interested in optimal, not maximum, yields and with our rapid successions and rotation we have so far been rather happy with the results.”
As an example of optimal yields, Leann and KIaus usually harvest their onions, transplanted 2” apart, as green onions to make room for another crop even though the green onions produce less income than mature bulbs. The Karbaumer’s long growing season makes it possible to follow green onions with winter squash and then a fall crop of green beans. Spring radishes make room for cucumbers followed by fall kale. Or spring spinach could precede summer seed- ing of beans and then a fall planting of beets. Klaus shared the average yields and current prices for some of their crops, all grown without irrigation.
With the exception of Walt Bernard and Kris Woolhouse of Ruby and Amber’s Farm in Dorena, OR, all of the teamsters in this plant density study rely entirely on hand tools for cultivating multiple row plantings or intercropped vegetables. In the Spring Small Farmer’s Journal, Walt introduced their revolutionary G Haw Tool Carrier specifically designed for cultivating multiple row beds with horses. For more details on this well-conceived and engineered implement plus videos of the G Haw in action working 1, 2, 3, and 4-row beds of vegetables, visit the farm’s Facebook page or website: workhorseworkshops.com.
Kris and Walt use the G Haw to cultivate multiple row beds on 48” centers, comparable to the new wave of tractorless, super intensive systems which rely primarily on human power for tillage and cultivating or maintaining a permanent mulch of compost. The plant density chart includes two examples: Les Jardins de la Grelinette in Saint-Armand, Quebec, the focus of Jean-Martin Fortier’s excellent book, The Market Gardener; and Tobacco Road Farm, Bryan and Anita O’Hara’s innovative no-till market garden featured in the Winter Cultivating Questions in Small Farmer’s Journal.
When selecting crops for this plant density comparison, we made the mistake of assuming most vegetable farmers transplant broccoli, lettuce and onions. As it turned out, the Asmus’ direct seed lettuce for salad mix and heads unless it is too cold for good germination, and they do not grow onions, thus the substitution with leeks on the chart. The Karbaumers do not bother with broccoli in their hot climate and direct seed other brassicas, such as kale and fall cabbage. Like the Asmus’, they sow lettuce for leaf production, letting select plants grow in to marketable heads. The choice of crops and how to plant them is often market driven as Bryan O’Hara explained in his correspondence:
“We don’t actually grow that much broccoli because of low profitability at current wholesale prices, a little bit for farmer’s market. Lettuce heads at that spacing are even more rare since we only wholesale cut lettuces in the form of salad greens, with only occasional head production for farmers market. The onions, however, are planted intensively at these spacings and the yields are very high! Generally at harvest you can barely see the soil in the beds because they are almost totally covered in onions!”
In Walt Bernard’s letter he cautioned that yield and price are not the only factors that influence planting decisions. “One comment I would mention is that planting density and yield are only part of the equation. There are other variables to consider, such as ease of cultivation, harvesting, packing, quality, etc… that might lead one to consider not planting in as high density. In other words, net profit per crop and net profit per crop area might take precedent over getting maximum yield per area, if the higher density planting leads to a higher cost of production or cost of harvesting or packaging.”
Walt’s reminder about the cost of production reinforced our decision to close this column on cropping diversity with a comparison of single row versus multiple row inputs and management we put together for the Fall 1999 Small Farmer’s Journal with the help of fifteen experienced growers using tractor, horse and human power. We are sure that today’s market gardeners could add to the list and might disagree with some of the group’s conclusions. Our reason for recycling this dated comparison is to show that the decision whether to plant intensively or extensively involves a lot more factors than just the choice of the power source.