Organic Broadcaster

Transplants offer jumpstart; transplant systems vary

By Chris Blanchard, Flying Rutabaga Works

The long and miserable spring of 2013 high­lighted the value of transplants for vegetable production in the Upper Midwest. Many farm­ers didn’t get into the field until mid-May—and then only for short periods of time. Those who had a weather-independent way to get vegetable crops up and running had a huge advantage; transplants provided a jump on the weather and the weeds that was impossible to get with direct-seeded crops. And, when the weather turned from flood to drought, growers who had transplant systems could germinate seeds without having to irrigate large tracts of land.

To help producers evaluate and select trans­plant production systems, I recently worked with the Iowa Organic Association and the Leopold Center for Sustainable Agriculture to develop The Transplant Production Decision Tool (Iowa Organic or Leopold Center for Sustainable Agriculture). This online tool provides information about the systems available for market farmers as they scale up to meet the increasing demand for local and organic produce. To gather information for this project, I visited several Upper Midwest growers to evaluate their transplant production systems, and to gather real-world information about what worked and what didn’t.

Transplant production systems involve compo­nents and related steps—growing trays, pot­ting soil, seeding methods, germination tools, bench design, irrigation tools and methods, hardening-off methods, and setting the plants out in the field—that have to work together to provide results that work in the larger context of the operation.

For small- and mid-sized growers, the compo­nents of the system are often drawn from multi­ple suppliers and manufacturers, and the parts don’t always fit smoothly together. At Vermont Valley Community Farm in Blue Mounds, Wis., Barb and Dave Perkins use injection-molded Plantel-brand flats for transplant production. While they have several advantages—including longevity, space efficiency, and ease of sanita­tion—the Plantel flats are an odd size: 9 by 26 inches. Commercially available germination chambers and plate seeders are most commonly designed to fit the more standard 10-inch by 20-inch or 13-inch by 26-inch trays, so Barb and Dave have had to manufacture their own versions of these tools.

Every system has its weak link. Investments can strengthen the weak link in a chain, but as soon as that link is strengthened, another one becomes the weakest—sometimes the new weak link appears as a direct result of the action taken to strengthen the previous weak link. At Rock Spring Farm, we used soil blocks to produce over 100,000 transplants every year. These lightly compressed blocks of pot­ting soil supported fantastic transplants, but making the blocks required a lot of skill and labor. When management transitions made this high-skill labor into our weakest link, we changed over to a cell-tray production system, whereupon we discovered that our new weak­est link was the relatively small amount of soil in each cell, which required more careful nutrient and water management.

Sometimes you need to create your own tools to fit your transplant system. Gardens of Eagan staff made this plug popper to extract soil plugs quickly. Photo by Angie Sullivan.


Systems needs to be easy to use, and should be designed to create consistent, reproducible results. At Harmony Valley Farm, Richard de Wilde and Andrea Yoder use a fan-shaped nozzle to water transplant trays. Most water­ing nozzles use a circular pattern to water square trays and cells; when they travel in a straight line, the center of the circular pat­tern puts out relatively more water than the outer edges of the circle, making it difficult to achieve even watering in every cell. The rectangular, fan-shaped nozzle provides more consistency along the width of its pattern, so that even an amateur irrigator can achieve consistent results.

Tools designed to reduce labor and increase other efficiencies enhance good management, but they can often amplify bad management. Two of the farms in the study installed auto­matic watering systems the year after I visited them. Both farms installed a timer so that they could turn the system on, then walk away from it while the sprinklers ran for a set amount of time before the system turned itself off.

Unfortunately, the greenhouse managers on both farms would set the irrigation system to run for a set amount of time each morning and afternoon, regardless of weather conditions and without regard to the variations in plant maturity, cell size, and water usage—all things that they would have observed closely if they were watering by hand. At both farms, this re­sulted in major problems with damping off and nutrient leaching, resulting in stressed and stunted plants in half-full growing trays. (One farm subsequently abandoned their automatic watering system; the other began varying water application duration and timing accord­ing to the weather, and followed up with spot watering as necessary.)

As a vegetable operation grows in size, the pres­sure of growth often drives investment in more efficient tools and equipment. There aren’t any hard-and-fast rules about the number of transplants you should be growing before investing in a given piece of equipment. I’ve seen 80-acre vegetable farms relying on flimsy, vacuum-formed flats and water wheel transplant­ers, and 30-acre farms that have invested in top-of-the-line injection-molded trays and carousel transplanters.

Labor-efficiency investments on a farm don’t necessarily provide a simple return on invest­ment. In an environment where weather can be unpredictable, even a very small operation can realize outsized benefits from the ability to get a large number of plants in the field in a short period of time. In a year like 2013, that can make the difference between having and not having a crop.

Opportunity costs also add up, and invest­ments in tools like a more efficient transplanter can free up machinery and personnel to tend to other important tasks. Vermont Valley bought a Mechanical 5000 carousel transplanter early in their operation. These expensive units can put thousands of transplants in the ground every hour, and most small growers don’t con­sider them to be scale-appropriate. Barb and Dave bought a one-row unit, which they offset to one side of the tool bar. Dave would drive each bed in one direction while Barb fed plants into the machine, then they would turn around and come back on the same bed. In this way they planted two rows on each bed much more efficiently than they could have with any other tool. As the farm grew and added additional employees, they added additional row units to the same tool bar.

When thinking about opportunity costs and investments, it may pay to buy some of your transplants. The first transplants of the year, when you heat your whole greenhouse to produce a fraction of its capacity, are the most expensive plants to grow. It might pay, too, to outsource some of the more high-skilled or precision-oriented tasks—like growing toma­toes or getting exactly three onion seeds in a cell—to an experienced operator or somebody who has the equipment to do it quickly and efficiently.

This article grew out of a project funded by the Leopold Center for Sustainable Agriculture as part of a grant to the Iowa Organic Association. Established by the 1987 Groundwater Protection Act, the Leopold Center supports the development of profitable farming systems that conserve natural resources.

Chris Blanchard provides consulting and education for farming, food, and business through Flying Rutabaga Works. As the owner and operator of Rock Spring Farm in Iowa for over 13 years, Chris raised 20 acres of vegetables, herbs, and greenhouse crops, marketed through a 200-member year-round CSA, food stores, and farmers markets.


January | February 2014

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