Promoting sustainable development and the
wise use of natural resources
Promoting sustainable development and the
wise use of natural resources
1. High Tunnels - Using low-cost technology to increase yields, improve quality and extend the growing season. Blomgren and Frisch. 2007. 74pp.
This paper was written through a grant with USDA Northeast Region Sustainable Agriculture Research and Education program (NE-SARE). It is a collaborative effort between extension and non-profit personnel with extensive input from northeastern farmers growing in high tunnels. This paper highlights the experience of high tunnel growers in the northeast from southern Pennsylvania to northern Vermont and uses detailed descriptions of their operations as case studies to present information about farming in high tunnels.
The first case study is from Cramer’s Posie Patch, a cut and dried flower farm in Pennsylvania, and provides a detailed description of their operation from cultivation and planting to pest control and harvest. The Posie Patch is known for its cockscomb (celosia), sunflowers, chili peppers, lisianthus, dahlias, and hydrangeas. The challenges for this farmer were mitigating heat, labor expenses and availability, and the uncertain timing of fall frosts with predicting flower availability.
The second case study is from Weaver’s Orchard where they grow a variety of tree, bramble, and tabletop fruits but the primary crops are apples and cherries. Multi-bay Haygrove high tunnels were built because they needed a way to protect their yields from frost, rain, and birds. Effectively growing tree fruits (delicate cherries in particular) in Haygroves was a learning process that had advantages and disadvantages but resulted in overall increases in the quality and quantity of fruit that led to the high tunnels being cost-effective. Specific high tunnel advantages for Weaver’s Orchard were early ripening, increase in weight and shelf-life of fruit, decrease in rain cracking, decrease in bacterial canker, and frost protection for blooms and fruit all resulting in higher market prices. Disadvantages for the Weaver Orchard were increased heat around harvest which softens berries, more complicated tractor operations, additional pollination needed, time-consuming logistics of managing the plastic, and experiential time needed to understand differences between field production and plasticulture such as varietal selections, planting density, and agricultural practices.
The third case study is from Cedar Meadow Farm in Holtwood, Pennsylvania. Cedar Meadow is a no-till farm that produces tomatoes, pumpkins, and sweet corn. Due to no-till soils being colder and having later harvests, Cedar Meadow was looking to offset the late harvests by using a high tunnel to encourage earlier harvests. Cedar Meadow has been able to document the amount of time and labor necessary to remove and cover the high tunnels seasonally and ventilate them properly based on temperature, wind speed and direction, and the stage of crop growth - narrow windows during critical the fruit-setting period.
The fourth case study is from Intervale Community Farm, located in Burlington, Vermont, and is the state’s largest CSA. They use gothic-shaped structures for growing tomatoes because they are a favorite of their customers. Specifics regarding commercially growing tomatoes in high tunnels are provided with information on seeding, planting layout, mulching, transplanting, and tomato varieties. Intervale Community Farm is also working on how to generate winter crops of salad greens.
The fifth case study is from microfarm Star Light Gardens in Hartford, Connecticut. They have five high tunnels in intensive vegetable production as well as field production. Salad greens are tomatoes are their main crops. They have experimented with overwinter production and heat one of their high tunnels. Marketing to and participation in farmer’s markets, restaurants contracts, and university dining programs have been the main part of their sales.
The sixth case study is from Slack Hollow Farm in Argyle, New York, which has two high tunnels and 15 acres in vegetable production. Their high tunnel crops are salad greens in the fall and tomatoes/basil in the summer. One of their high tunnels is particularly innovative in that they heat their soil with heat tubes that warm the soil and the root zone. This heating of the soil has transformed their farm model with year-round production; ultimately, allowing them to keep year-round employees that are focused on the winter production and marketing but most importantly allowing them to take time off during the winter and travel.
Each of the case studies really highlights the time it took to refine the new agricultural practices needed to grow in high tunnels. While initial productivity increases were high so were concurrent increases in labor, time, and management. In all the case studies, it took many years and growing seasons to figure out how to make operations efficient, productive, and cost-effective.
In addition to the case studies, the authors explain the basics of high tunnels including several types of high tunnels and the benefits of using high tunnel systems. There are good definitions of high tunnels and their benefits: season extension, protected microclimate for plants and workers, higher yields and quality, and fewer pests. There is also consideration given to marketing, site considerations, selecting your structure, construction tips, environmental management, soil and crop management, and pest management.
Marketing – One of the advantages of high tunnels in the continental US, is that they extend the growing season. Advertising a unique commodity such as early or late tomatoes, can be an effective way to introduce customers to the farm operation. Traditional low-cost advertising avenues such as brochures, websites, social media, and signage are usually all that is required. Farmer’s markets are great venues to sell local produce directly to customers; however, success at markets often involves being innovative and flexible and offering products that other vendors do not have. High tunnels growers should anticipate the next opportunities to stand out from fellow vendors. Farmers may need to develop their own markets at times including pick-your-own, CSA, restaurant sales, and wholesaling.
Site Considerations - Selecting a suitable site is critical to efficient high tunnel operations and optimal growth. Well-drained soil, full sun, and wind (for protection and ventilation) are physical factors that need to be considered. Proximity to water and electricity, equipment and personnel access, room for expansion, snow removal, run-off are all factors that need to be part of the high tunnel site plan.
Selecting Your Structure - How to select a structure based on your space, time, and growing area. The authors discuss several brands of high tunnels, walk-in tunnels (caterpillars and how to build them), and low tunnels.
There is a section on selecting high tunnel materials such as frames, plastics, baseboards, end walls, covers, and detailed construction tips. The authors estimate that “two people with good construction can erect a 30’x96’ high tunnel structure (not including site preparation, the plastic covering, or other utilities) in one week, assuming all materials are on site and a completion time of 75-100 hours.” How-to descriptions are provided for batter boards, ground posts, bows, purlins, baseboards, and gable ends.
Once the high tunnel structure is built and covered, managing your high tunnel is discussed with tips for environmental management such as temperature (heating and cooling), ventilation (air control for pollination and disease management), and soil health (nutrient management and salt buildup). Potential plant layouts are also presented with information on planting (seed bed prep and watering). Integrated pest management is also discussed.
Lastly, this paper has an informative glossary and extensive resource list at the end of high tunnels/greenhouses, plastic film, supplies, irrigation, beneficial insects, seeds, tools, and informational publications.
