Season Extension and Cultivar Evaluations for Increasing Farmer Profitability Using High Tunnels in the Baltimore/Washington Metropolitan Marketing Area

Impacts of Results/Outcomes

The leaders of the project are confident that this project had a positive impact on increasing the adoption of high tunnels in the mid-Atlantic region and also adding to the knowledge base of extending the season for tomatoes grown in high tunnels. While 41 new high tunnels were built as a result our work (performance target of 40), there were many additional positive outcomes as a result of this project. Because of the outreach efforts of this project and the collaboration with Tom McConnell, Farm Management Specialist, West Virginia University Cooperative Service, four high tunnels were built in West Virginia to demonstrate high tunnels’ economic benefits to their vegetable farmers. We can assume that additional tunnels will be built by farmers in West Virginia as a result of the demonstration tunnels and these will add to our performance target total.

The initial plan developed by the project team leaders and the farmer cooperators was to grow early season tomato varieties so the cooperators would have tomatoes a month earlier for their marketing mix. Then as the production of these tomatoes diminished, they would remove them and replant with another variety better suited for late summer and fall production so the cooperators would have late tomatoes for their marketing mix after their field grown tomatoes were frosted out. In this project, each cooperator devised their own plan on how their high tunnel tomatoes would replace and or supplement their field grown tomatoes. At the end of this project some cooperators were growing one crop of tomatoes in their tunnels until mid July and then replanting with beans and greens for fall markets. Then other cooperators were growing tomatoes all season long in their high tunnel and planting greens in the tunnel for winter/spring sales. Each method was profitable and demonstrated the versatility of high tunnels to increase farm profitability.

During the three years of this project, the tomato varieties each cooperator selected to grow in their high tunnel were a large factor in their level of tunnel profitability. Some varieties produced well in the heat, some varieties produced well all season and some varieties were better suited to spring and early summer production. The importance of variety selection to meet the needs of the cooperators farm plan demonstrated the need to continue tomato variety trials in high tunnels. As a result of these findings, Bryan Butler, Maryland Cooperative Extension has begun an expanded high tunnel tomato variety experiment at three sites in Maryland to provide research based results to the mid-Atlantic region.

As a result of working together on this project, Butler and Davis recognized the need to better utilize the space in a high tunnel and at the same time grow additional high tunnel crops such as strawberries and greens up off the ground for easier harvesting. So Butler and Davis invented the “Strawberry Sling/Vegetable Hammock” growing system for high tunnels. This innovative “strawberry sling/vegetable hammock” is a practical low cost method for growing strawberries and vegetables up off the ground in a high tunnel. The “strawberry sling/vegetable hammock” is a specially designed landscape fabric material when hung inside the high tunnel provides a 6” wide growing area which is filled with potting mix. They designed a low cost way to hang the "strawberry sling" "vegetable hammock" in the high tunnel. This invention allows for farmers to construct the "strawberry sling" "vegetable hammock" themselves to meet their specific requirements of length, height and location in the high tunnel depending on current crop production. The “strawberry sling/vegetable hammock” can be easily removed after use and and or moved to a different location in the high tunnel. It also allows for the more efficient use of space in a high tunnel structure. There are 30 “strawberry sling/vegetable hammock” being used in high tunnels on farms and university sites in Maryland, West Virginia and Utah. The results from these units clearly show that the “strawberry sling/vegetable hammock” work as designed and are profitable additions inside a high tunnel. The sales of the “strawberry sling/vegetable hammock” to high tunnel farmers may spawn a potential business in the near future.

While the main goal of this project was to research season extension for tomato production in high tunnels and also to increase the number of high tunnels in the mid-Atlantic region, five additional and important research results emerged from this project mainly due to problems we encountered during 2005 and 2006 growing seasons. The first research result was finding a source of healthy transplants when planting earlier than customary in a region. Because we were planting tomatoes 4 to 6 weeks earlier than field grown tomatoes, transplants needed to be started in mid February, which meant finding a greenhouse operation capable and willing to grow our transplants. The project team and cooperators decided all of the transplants should come from the same source to help insure standard size and quality. A local transplant source was found and contracted to grow the first years transplants to meet each cooperators planting date and the transplants were delivered to the cooperators by Mark Davis. Eight weeks after tomato planting, while making her routine farm visits, the project technician noticed two of the cooperators tomatoes were stunted and not growing. Plant tissue samples were taken from both cooperators and sent to the University of Maryland Diagnostic Laboratory (UMDL) for evaluation. The lab results indicated both cooperators’ tomatoes were infected with “Tomato Spotted Wilt Virus” (TSWV). TSWV was not common to this area, the source of this infection should be located, and the tomatoes would not grow out of this and was highly contagious to surrounding tomatoes. The lab recommended the cooperators destroy the tomatoes and the remaining cooperators tomatoes also should be tested. The two cooperators destroyed their tomatoes and tissue samples were taken by the technician for analysis and they also came back positive for TSWV. Project leaders working with UMDL determined because all of the cooperators tomatoes were infected the source of the infection had to be the greenhouse operation that grew the transplants. Project leaders met with the greenhouse owners and found over-wintering ornamentals were also in the greenhouse where the transplants were grown, and were the likely hosts harboring the insects carrying the TSWV virus. Further discussions with the greenhouse owner determined this was the first time he had grown tomato transplants this early in the season and was not aware the ornamentals would cause a problem. The interesting “rest of the story” is the remaining two cooperators whose tomatoes tested positive for TSWV, did not destroy their tomatoes because they did not show signs of the disease. Their tomatoes remained visually healthy and continued to yield profitable excellent quality tomatoes for most of the season. The project team leaders analyzed all of the cooperators soil tests and found interesting results. The two cooperators whose tomatoes were stunted and stop growing and later destroyed, their soil test results indicated adequate fertility for tomatoes inside their high tunnel. And their high tunnel in season fertility program was the same as their field grown tomato fertility program, minimal additions according to past experience. The two cooperators whose tomatoes were unaffected by the TSWV had exceptional fertility inside their high tunnels and their high tunnel in season fertility programs kept their fertility levels high throughout the growing season. Their tomatoes grew vigorously as soon as they were transplanted; “just looked good” all season and the only answer the project team can find is the TSWV never had a chance to affect growth and yield because of high the fertility throughout the season.
The second research result is communicating with your neighboring farmers what you are doing with your tunnel. During the 2005 season, one farmer cooperator had their tomatoes destroyed inside their high tunnel a week after transplanting by 2,4-D spray drift from an adjacent field being sprayed for no-till corn production. 2,4-D is a common herbicide used as part of a tank mix for no-till corn production and after application when conditions are right 2,4-D will volatize and drift in the air and move to surrounding areas. Most trees and household shrubbery will tolerate 2,4-D drift, but tomatoes are highly susceptible to a even small amount of 2,4-D in the air and young transplants are the most susceptible, “Just a whiff” can curl and stunt tomatoes and they die slowly. When the cooperator talked with the neighboring farmer about the spray drift, the neighboring farmer was unaware of the cooperators high tunnel and would have changed his tank mix to not include 2,4-D. This problem could have been avoided if our cooperator would have communicated with his neighbor. In an area of highly-concentrated established grain production it would benefit farmers who build high tunnels to make a point to visit with their neighbors and describe their plans with them so problems like this can be avoided.

The third research result is “Nip it in the Bud”. Many market garden farmers are sustainable or organic farmers. And both types of farmers have developed insect management strategies that minimize or use no pesticides in their field production. This mainly consists of over-planting for yield compensation and allowing the natural insect predator/prey cycles to occur. These strategies at least minimize crop loss from insect damage to a tolerable level. This strategy will not work within a high tunnel. Through observation, the tolerable insect threshold level for a high tunnel is lower than in the field, and this may be since the high tunnel is a semi enclosed environment. During this project, when insect numbers reached threshold level, the cooperators who sprayed early as recommended by Butler to minimize the insect damage, were rewarded for their efforts with healthier plants which continued to yield high quality fruit longer into the growing season. The cooperators who did not spray in a timely manor or who chose not to spray, had stressed plants with reduced yields and decreased plant life. These results were true with both sustainable and organic farmers alike. It must be noted that in all of the high tunnels there were beneficial insects present at most times during the warmer growing season, but the beneficial insects did not increase as fast as the pest insects when pest insect numbers increased past threshold level. The project leaders borrowed the “Nip it in the Bud” term for managing insect problems. Farmers taking quick action to stop an insect problem early will be rewarded in a high tunnel with increased profits.

The fourth research result is increased yield and fruit quality from crops grown in a high tunnel when compared to field production. The tunnels’, which keeps the crops foliage dry, helps to promote conditions that reduce disease. By controlling moisture through drip irrigation, a high tunnel is a concentrated growing environment with the potential for high production and excellent fruit quality. This is true with both tomatoes and the supplemental crops grown in high tunnels by the cooperators. Cooperators who grew heirloom tomatoes noted the high tunnel tomatoes cracked less, had fewer blemishes and had increased yields when compared to their field grown tomatoes. Supplemental crops included pea shoots, carrots, rapini, strawberries, beans and salad greens, and cooperators also noted improved quality and increased yields from these crops. Strawberries especially had less disease, increased yields and earlier harvest date when compared to field grown strawberries. Salad greens also had increased quality, yield and extended season when compared to field grown greens.

And the fifth research result is “Good high tunnel management is key”. By the conclusion of this project it became increasingly obvious to the project leaders that as cooperators devoted increased time managing their high tunnel, crop quality and yields increased and therefore profitability also increased. Good high tunnel management is defined as rolling the sides up and down for maximum heating and cooling, monitoring the crops for disease and pests problems, developing an irrigation schedule, fertility management and the timely harvesting of crops. Good high tunnel management is not just spending 10 minutes in the morning to turn on the irrigation and walk through the tunnel, and coming back 3 hours later to turn off the irrigation and to harvest. As the growing season progresses and farmers need to devote increased time for field production, there is the potential management conflict between high tunnel and field production. How each farmer manages to balance their limited time between the high tunnel and field production plays an important role in the success of their high tunnel.

Economic Analysis

Since the five cooperators’ harvesting methods and supplemental crops varied greatly to meet their marketing needs the project team leaders decided to employ a case study approach for the economic analysis. Project team leaders and farmer cooperators decided the economic benchmark for a “successful high tunnel growing season” would be total gross sales from the high tunnel to meet the total cost of building a 21? x 48? high tunnel, which was selected as the standard growing area for data collection. Butler and Davis reviewed the building costs for the projects tunnels, including lumber, plastic, and end wall construction and determined the average total cost for a 21? x 48? high tunnel was $3,000, so a $3,000 gross income was accepted by all as the economic benchmark to be used for the economic analysis. As one cooperator stated, “The crops sales from the tunnel should pay for the tunnel each year”.

Case study 1, Cooperator A: 2005 was the first year of the project and cooperator F planted tomatoes on March 23, 2005, as scheduled. Early in the season this was the first location to give us some indication there were problems as their tomatoes were stunted and stopped growing. The tomatoes were diagnosed as having “Tomato Spotted Wilt Virus” (TSWV). Project leaders advised cooperator A to remove the tomatoes and also remove any other vegetation inside the high tunnel and to mow the area surrounding the high tunnel to keep the TSWV from spreading. Project leaders also communicated with cooperator A about their lack of management in the tunnel and discussed a plan with the cooperator for timely replanting of the tunnel to best utilize the tunnel. The cooperator was very slow to remove the tomatoes and did not replant the tunnel. Cooperator A harvested a total of 197 lbs. of tomatoes @ $3.00/lb. and a total income of $591. Cooperator A did not participate in the remaining two years of the project.

Case study 2, Cooperator B: In 2005 cooperator B planted tomatoes on April 1 as scheduled. Cooperators B started by harvesting large yields of tomatoes for two weeks. The tomatoes began to show signs of TSWV and tested positive also. Cooperator B was concerned that TSWV would be transmitted to their outside tomatoes. They pulled out the plants when they began to show signs of TSWV and when their outside tomatoes started to ripen. This made for a smooth transition and the disease did not spread to their outside production. In the two week harvest period, 466 lbs. of tomatoes were collected @ $3.00/lb. for a total income of $1,398. In the middle of discussions with cooperator B on replanting the high tunnel, unexpected management changes occurred at this location and it became apparent cooperator B would be unable to continue in the project.

Case study 3, Cooperator C: In 2005 Cooperator C planted the tomatoes in the high tunnel as scheduled and then their tomatoes were destroyed by 2,4-D spray drift from an adjacent field being sprayed for no-till corn production. Project leaders encouraged cooperator C it would still be beneficial to replant the high tunnel with tomatoes. Cooperator C did not replant their tunnel because they were busy planting their field tomatoes and other crops. Cooperator C did plant the high tunnel in spinach in the late summer for their fall market mix and for a winter farmers market in Washington D.C. Cooperator C harvested 560lbs. of spinach @$10.00/lb for total high tunnel income of $5,600. The 2005 fall season was mild and the 2006 winter was very warm and as a result the high tunnel spinach crop yielded exceptionally well, and also because of the warmer than normal winter attendance and sales from the winter market were outstanding. Cooperator C planted their tomatoes on April 1, 2006. They began harvesting tomatoes on June 22 and stopped on November 25, 2006. They harvested 6532lbs. from the three rows @ $3.00/lb. for a total income of $19,596. During the 2006 growing season the management in this high tunnel was superb. Cooperator C or an employee spent significant time to prune, stake, tie, control diseases and insect pests in the tunnel. The two tomato varieties, Moskovich and Prudens Purple chosen by cooperator C yielded exceptionally well, both early and late in the season. The tomatoes were trellised up to a height of eight feet. This example shows the potential of growing tomatoes in a high tunnel when exceptional management and time is spent in the high tunnel. In 2007, cooperator C planted their tomatoes on April 3. The harvest period began on June 22 and continued until November 15, 2007. A total of 2276 lbs. tomatoes were harvested @ $3.00/lb. for a total income of $6,828. Cooperator C admitted to project leaders because of labor issues, less time was spent in the tunnel in 2007 than in the previous year.

In summary, cooperator C exceeded the $3,000 gross income from their tunnel for each of the three years of the project. While 2005 began as a disaster, it ended profitably due to an excellent spinach season and lucrative markets. In 2006 and 2007 the high tunnel tomatoes allowed cooperator C to have tomatoes to sell three to four weeks earlier than their field tomatoes. Tomato yield and income from 2006 was unbelievable, a once in a lifetime crop and tomato yield and income for both 2006 and 2007 more than doubled the established $3,000 economic benchmark.

Case study 4, Cooperator D: In 2005 cooperator D planted tomatoes on April 15 and they grew as expected early in the growing season. These tomatoes also tested positive for TSWV but continued to grow and produce adequate yields for a five week period. By this time their field tomatoes were producing and cooperator D removed the tomatoes from the high tunnel. Cooperator D harvested 425 lbs. of tomatoes @ $3.00/lb. for a total income of $1,275. Cooperator’s D harvest period began on July 22 and continued until August 30. Cooperator D had early tomatoes for their markets, but not as early as they anticipated. They hoped to plant earlier in 2006. Cooperator D planted beans in the tunnel after tomatoes and harvested 300 lbs. @ $5.00/lb. for income of $1,500. Cooperator D’s total tunnel income was $2,775 for 2005. Cooperator D planted their tomatoes April 1, 2006, two weeks earlier than 2006, and their harvest period was June 23 to July 28. They only harvested 172 lbs. of tomatoes @ $3.00/ lb for a total income of $516.00. These low yields were due to many problems throughout the season. Cooperator D buried a new type of drip tape under the tomato plants and the watering pattern was very uneven, which led to stressed plants. Some plants received too much water and some plants received too little water. Cooperator D had to replant a portion of tunnel on April 12. The 2006 winter was mild and the summer heat began early and insect issues came to the forefront early in the season in the tunnel, as aphids, then whiteflies, then mites, then tomato rust mites became problems. Control options were presented to Cooperator D but they did not treat the insects or mites in a timely or effective manner and not only lost yield but also prematurely lost their tomato plants. Initially they did nothing, assuming the beneficial insects would control the insect problem, which is the same routine they follow with field production. But this did not work because insect problems in a high tunnel are magnified and the beneficial insects did not control the insects or mites. By this time the control options were not effective in controlling the insects or mites and the tomatoes were never able to recover. Then cooperator D was busy with field production problems as the summer continued to bring hot and dry weather to the area and the high tunnel would remain empty until fall. During the coldest portion of the winter, Cooperator D rolled up the sides of the high tunnel to freeze out any over wintering insects. Cooperator D harvested 200 lbs. of early spring kale @ $3.00/lb. for income of $600; this combined with the tomato income of $516 gave a total high tunnel income of $1,116 for 2006
2007 was a better year for cooperator D as they planted their tomatoes on April 3, with a harvest period beginning on June 21 and ending on October 5, 2007. No major management or production issues occurred during the 2007 season and cooperator D harvested a total tomato yield of 1,387 lbs @ $3.00/lb for a total income of $4,161.

In summary Cooperator D had early tomatoes with excellent quality and good quantities for their markets the last year of the project. They also worked through many high tunnel management issues during the three years of this project. Cooperator D has the largest field production of all of the cooperators in this project and best illustrates the management and labor issues that continually need to be balanced during the season between the field and high tunnel and that this balance may greatly effect the level of profitability from a high tunnel.

Case study 5, Cooperator E: In 2005 cooperator E planted their high tunnel tomatoes on April 1 and their harvest period began on June 9 and ended on November 15. They harvested 1249 lbs. of tomatoes @ $ 3.00/lb. for a total income of $ 3,747. Their tomatoes were also diagnosed as having TSWV but did not show signs of the disease until late in the season. Cooperator E had excellent fertility in the high tunnel and continued to fertilize the tomatoes during the season. Cooperator E’s high tunnel tomatoes were excellent quality and three to four weeks earlier than their field tomatoes.
Cooperator E planted their tomatoes on March 28 and their harvest period began on June 29 and ended on August 29, 2006. Insect issues were less of a problem for Cooperator E, who was were quicker to respond to the problem and remained diligent and continued to treat the insect problem during the season. Their harvest period for 2006 was much shorter than 2005 because they wanted to plant greens in the tunnel for their early fall markets, and their field tomatoes were producing well. They harvested 878 lbs. of tomatoes @ 3.00/lb for a tomato income of $2,634, and sold $712 of fall greens for total income for 2006 of $3,346. In 2007 Cooperator E planted tomatoes on April 23 and their harvest period began on June 6 and ended on October 15. They harvested 908 lbs. of tomatoes @ 3.00/lb for a tomato income of $ 2,724. They also planted both edges of their tunnel in spring chard and harvested 250 lbs. of chard from April 23 to May 9 @3.00/lb for income of $750 for a total high tunnel income of $ 3,474. Also cooperator E has found an additional use for their tunnels in the spring, as the tunnels offer an excellent location to store transplants. Last year cooperator E sold $8,000 worth of tomato, pepper, basil, eggplants at market in April and May. None of that would have been possible without the tunnels.

In summary Cooperator E was the most consistent cooperator in the project. Their high tunnel management was excellent throughout this project. The high tunnel tomatoes were of higher quality and increased yield when compared to their field grown tomatoes, especially the heirloom varieties. Cooperator E exceeded the $3,000 economic benchmark for all three years of this project and has built another high tunnel.

Case study 6, Cooperator F: Cooperator F joined the project in 2006 replacing cooperator A. Cooperator F planted tomatoes on April 3, with a harvest period beginning June 21 and ending on July 31. They harvested 893 lbs. of tomatoes @ 3.00/lb for tomato income of $2,679. They also sold $360 of fall spinach for total high tunnel income of $3,039. In 2007 Cooperator F planted tomatoes on April 2, with a harvest period beginning June 30 and ending September 15. They harvested 1493 lbs. of tomatoes @ $3.00/lb for tomato income of $4,479. They also harvested 60 quarts of strawberries from May 3 to June 7 @ $5.00/qt. for additional income of $360. Cooperator F’s total high tunnel income for 2007 was $4,779.
Cooperator F’s high tunnel income for 2006 and 2007 exceeded the $3,000 economic benchmark for success of this project. Improved quality and increased quantity of tomatoes harvested from the high tunnel make high tunnel tomato production a profitable method for growing tomatoes according to Cooperator F. Cooperator F was an enthusiastic and supportive addition to this project.

Case study 7, Cooperator G: Cooperator G joined the project in 2006 replacing cooperator B. Cooperator G planted tomatoes on March 24, with a harvest period beginning June 6 and ending on August 23. They harvested 540 lbs. of tomatoes @ 3.00/lb for tomato income of $1,620. They also sold 298 pts of strawberries @ $4.00/pt. for income of $1,192 for total high tunnel income of $2,812. In 2007 Cooperator G planted tomatoes on April 4, with a harvest period beginning June 7 and ending November 8. They harvested 1080 lbs. of tomatoes @ $3.00/lb for tomato and total high tunnel income of $3,240. Cooperator G’s high tunnel income for 2006 was slightly less than the $3,000 economic benchmark but their 2007 high tunnel income was slightly above the $3,000 economic benchmark for success of this project. Cooperator G was pleased with their high tunnel tomato and strawberry results. Cooperator G was fine addition to this project.

In summary: In each of the three growing seasons, there were three factors that promoted profitability: 1. The cooperators decision to plant supplemental crops thus providing additional income for the season played an important role the overall profitability of the high tunnel. 2. How each cooperator integrated their high tunnel, especially labor management into their overall farming system was also an important factor in profitability. 3. But the most important factor in whether a cooperator was successful in growing tomatoes in their high tunnel was the amount of time spent in the high tunnel for the entire season.

Farmer Adoption

The research team feels there were three contributions from this project for our beneficiaries. First, the research results are an important contribution in demonstrating the versatility and increased farm profitability from a high tunnel. Secondly, this project confirmed that an unheated high tunnel can extend the growing season both spring and fall for increased farmer profitability. And by doing so, increase the quantity of locally produced vegetables for consumers of the mid-Atlantic region, and enhancing the regions farmer markets for stronger communities. And last but no less important is the continued collaboration by the research team members and some cooperating farms on additional high tunnel research. This research project provided a strong foundation for high tunnel research by bringing researchers, cooperative extension and farmers’ together working on a common goal of utilizing high tunnels to extend the season and therefore increase farmer profitability.

Because the outreach activities of this project covered three states and included the high tunnel field events at cooperators farms and many presentations at meetings, it is difficult to give a definitive number on how many farmers have built high tunnels. But project team leaders can attribute 41 high tunnels being purchased as a result of this project.