Improving Seedless Cucumber Production to Diversify High Tunnel Crops in the North Central Region

Final report for LNC17-390

Project Type: Research and Education
Funds awarded in 2017: $200,000.00
Projected End Date: 09/30/2021
Grant Recipient: Purdue University
Region: North Central
State: Indiana
Project Coordinator:
Wenjing Guan
Purdue University
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Project Information

Summary:

Seedless cucumber has drawn great interest from farmers in the region due to its great marketing potentials. However, challenges in high tunnel cucumber production do exist. Disease and insect pests including bacterial wilt, powdery mildew, two-spotted spider mites; low soil temperatures in the early season; and high level of labor requirement have been obstacles preventing farmers from growing this crop in high tunnels. In this project, we optimized production practices for high tunnel seedless cucumber production. Approaches include 1) evaluated seedless cucumber cultivars of the different types. We investigated yield, resistance/tolerance to major disease and insect pests, quality and shelf-life of major cucumber types and cultivars; 2) evaluated pruning and trellising systems for growing seedless cucumbers; 3) investigated effects of using grafting technique to improve cucumber yield and extend production season. We also evaluated different rootstocks, the sensory property of grafted fruit, and the economic value of using grafting technology. Our results indicated that farmers should select seedless cucumber cultivars based on consumer preference, production systems, yield potential, disease resistance, and insect pest tolerance.  Pruning and trellising systems should be adjusted according to cultivars, available labor, and the anticipated harvest duration. Our research in using grafting technology in high tunnel cucumber production indicated that grafting is an effective approach to increase early-season cucumber production; hybrid squash rootstock is the most suitable rootstock for the high tunnel cucumber production system; sensory properties of cucumber fruit were not affected by grafting. Economic analyses suggested that grafting can be an economically feasible tool for high tunnel seedless cucumber production. During the process of conducting field trials, we reported a cucumber disease charcoal rot, caused by Macrophomina phaseolina in Indiana the first time. Five peer-reviewed journal articles were published, and one grant (LNC20-438) was funded as a result of this project. Farmer participation is an important component of the current project. A total of 22 on-farm trials involving 13 farms were conducted from 2018 to 2020. Of the farmers who directly participated on-farm trials, four farmers reported that they will incorporate cucumber grafting into their production system. Three farmers incorporated grafting practice, and one reported an above 90% success rate by grafting cucumbers on-site. Nine field days and workshops that highlighing this project were conducted in IN and IL. Farmers and agricultural professionals in IN, IL, OH, MI, MN, IA, and mid-Atlantic region received the project information through presentations at farmers’ conferences in the above states. At least 800 farmers and agricultural professionals directly received the project information. The project led to the publication of High Tunnel Cucumber Production Guide.

Project Objectives:

Objective #1: Establish production practices for economically growing seedless cucumbers in high tunnels.

1.1 Evaluate seedless cucumber varieties for yield, plant growth parameters and disease resistance. 

1.2 Optimization of pruning and trellising systems that can provide maximum seedless cucumber yield while minimizing disease and pest incidence.

1.3 Evaluate season extension relative advantage and yield potential of seedless cucumbers grafted onto commercial rootstocks.

Objective #2: Determine economic value of including seedless cucumbers into high tunnel cropping systems

2.1 Conduct partial budget and sensitivity analyses of systems required to grow grafted and non-grafted seedless cucumbers in high tunnels.

Objective #3: Develop and deliver an outreach program on diversifying high tunnel cropping systems through enhanced seedless cucumber production

3.1 Involves growers at planning, implementation and evaluation phases of the project.  

3.2 Deliver the research-based knowledge to a broader audience through multiple extension channels.

Introduction:

While high tunnels have become increasingly popular over the last 20 years as a valuable season extension tool, the considerable potential of this agricultural tool has not, to date, been fully realized. In this regard, the primary use of high tunnels to date has been to extend the growing season for tomatoes and winter-grown leafy greens, with lesser popularity of other vegetables [1]. As tomatoes have proven to be a crop with the capacity to provide excellent returns [2], growers are usually compelled to grow this single crop year-after-year. Continuously growing the single crop is frequently highly detrimental to soil health and increases risk of disease and pest problems. A classic example is tomato leaf mold which has become an important disease significantly contribute to tomato yield loss and quality reduction. 

While primary considerations for decisions regarding which vegetables to grow in high tunnels involve efficient space utilization in order to optimize profits, the establishment of optimal cultural practices is also an important consideration. High tunnel systems provide crops with intermediate environmental control. Such systems increase heat utilization and prevent challenges associated with rain, snow and strong wind. High humidity, no free water, and the wide range of day-and-night temperature differences serve to characterize high tunnel microclimate conditions. Because such conditions are significantly different than those in open-fields, suitable varieties and production practices commonly used in field production do not always apply to high tunnel production.

Unfortunately, except for tomatoes, relatively little information is available regarding variety selection and production practices for growing other vegetables in high tunnel systems. As a consequence, there is an increasing critical need to identify alternative crops and establish conditions that allow crops other than tomatoes to be adapted and grown profitably in high tunnel production. Not addressing the critical need would likely be problematic in advancing the sustainability of the high tunnel systems, as well as the roles they play in providing the local food community. Our central hypothesis in this application is that seedless cucumbers can be successfully and profitably grown in high tunnels and will generate adequate profit for both conventional and organic systems.

Seedless cucumbers, also called greenhouse cucumbers, are a popular and high-value crop in many local food markets. The plants are parthenocarpic with the capacity to set fruit without need for pollination. There are different types of seedless cucumbers. The cumbers with extended length are often referred to as European, Japanese or English cucumbers. They have thin skins with longitudinal ridges. They are often individually wrapped to prevent postharvest fresh weight loss. Beit Alpha cucumbers are smaller, with a range of sizes. Large Beit Alpha cucumber is similar to slicing cucumbers. Pickling cucumbers with the parthenocarpic character are also available in the market. Seedless cucumbers sell at premium price in early market as do tomatoes [3]. In addition, the characteristic climbing habit allows crop for trellising to maximize the use of vertical spaces, making seedless cucumber a potentially valuable crop for high tunnel production. Worldwide, seedless cucumber ranks third in the list of most important high tunnel crops following tomatoes and peppers [4]. However, because peppers and tomatoes are both in the Solanaceous family and share some of the same diseases and pests, cucumber would likely be a preferred crop to be rotated with tomatoes in high tunnel systems for the reasons summarized above.

At the present time, however, several challenges have prevented many growers from growing seedless cucumber in high tunnels. One particular challenge is the relatively low soil temperatures in early season that suppress plant growth even when the air temperature would be adequate for cucumber production. Soil temperatures lower than 63 °F greatly inhibit absorption of water and mineral nutrients of the crop [5]. In USDA plant hardiness zone 6, we found soil temperatures inside a high tunnel in April to frequently be below 55 °F, which prevents crop establishment and delays early cucumber production. In this regard, it may take eight to nine weeks for early spring-planted cucumbers to reach the harvest-stage, compared to approximately six weeks for the later-planted vines. As a result, it is usually difficult to achieve the early-season advantages for growing cucumbers in high tunnels. To overcome this obstacle, a system for heating the soil within the high tunnels is essential for early production of seedless cucumbers in Europe. However, this approach requires additional energy input and is, therefore, less sustainable for high tunnel growers in the North Central Region. Disease and pest problems are additional challenges that prevent growers from growing cucumbers in high tunnels. Among them, powdery mildew, two-spotted spider mites and bacterial wilt are the most common and destructive pest problems. Since many high tunnel growers are using organic approaches, they are even more vulnerable to these disease and pest-related damages.

Vegetable grafting is a cultural practice commonly used for controlling biotic and abiotic stresses. By physically conjoining a plant with desirable fruit characteristics (called a scion) onto another plant with specific disease resistance or stress tolerance (called a rootstock), grafted plants acquire the capacity to combine the beneficial characteristics of both the rootstock and scion cultivars [6]. Most commercial rootstocks (Cucurbita maxima or C. mochata) developed to date for cucumber grafting have demonstrated cold tolerance. Grafting cucumbers onto these rootstocks could potentially help to enhance early season cucumber production. Results from our preliminary study have provided some evidence that grafted cucumber seedlings can be successfully grown in high tunnels even when soil temperatures were in lower 50 °F. The grafted plants that were transplanted in high tunnels at the end of March started to produce cucumbers in early May (~6 weeks), and the seasonal yield was significantly higher than that of non-grafted plants. 

Vegetable grafting was introduced in the U.S. in the 1990s. Over the years, farmers have become increasingly familiar with the technique. In addition, Sustainable Agricultural Research and Education (SARE) has funded 13 projects related to tomato grafting. These projects have achieved great success by introducing this technique to small farmers in the U.S. A number of tomato farmers, especially those growing tomatoes in high tunnels, have successfully adopted this technology. These funded projects have primarily focused on control of soilborne diseases. In discussions with farmers who have adopted the technology, we found that they actually know relatively little about grafting cucurbit crops, nor the use of this technology to enhance crops’ tolerance to suboptimal temperatures. In the proposed project, we will build on the previous SARE funded projects on vegetable grafting, and expand the scope of the research from tomatoes to cucumbers, and from disease control to suboptimal temperature tolerance.

Bacterial wilt is one of the more destructive diseases in cucumber production. The pathogen (Erwinia tracheiphila) are vectored by cucumber beetles. Infected plants wilt and die in only a few days. Cucumbers and muskmelons are generally more susceptible to bacterial wilt than watermelons, pumpkins and squashes. Our preliminary field trials conducted by Laura Ingwell have found that grafting cucumbers onto bacterial wilt-resistant watermelon reduced the number of cucumber beetles per plant and the incidence of bacterial wilt. One mechanism that has been identified to provide resistance against bacterial wilt is plant growth-promoting rhizobacteria (PGPR) induced systemic resistance. It reduces concentrations of beetle feeding stimulant and activates plant defense mechanisms after the pathogen has been introduced [7]. The systemic resistance may also exist in grafted plants. One evidence is the expression of plant defense responses-related proteins was significantly higher in C. moschata grafted cucumbers compared with self-rooted plants [8]. Although the underlying mechanisms are still largely unknown, the applicability of grafting to control bacterial wilt in cucumber production warrants further investigation.

A limitation of using grafting as an approach to improve crop characteristic is the potential negative impact on fruit quality. Currently, relatively little information is available in this respect with regard to cucumbers. Considering that cucumbers are routinely harvested as immature fruit, the rootstock effects on sugar contents might be negligible. But other vegetable quality attributes including firmness, fruit appearance and sensory property need to be evaluated.

Powdery mildew and two-spotted spider mites are known to cause significant damage to cucumbers grown in protected agricultural environments. Both pests prefer dry-atmosphere and higher temperatures, which are the predominant environmental conditions in high tunnels in the summer. Cucumbers have been shown to exhibit differential levels of relative resistance or tolerance to the two pests. For example, our primary data indicate that the pickling cucumber, ‘Excelsior’, is more susceptible to two-spotted spider mites than other varieties. But such types of information are not always presented or not adequately described in the seed packages. Comprehensive variety evaluation, with a focus on powdery mildew and two-spotted spider mites resistance/tolerance, would be of considerable importance in identifying those varieties that would be most suitable for high tunnel production.

Canopy modification through pruning and trellising can play a significant role in disease management. Dense plant canopies, for example, result in high relative humidity and low light intensity that are favorable conditions for powdery mildew development [9]. In addition, older leaves can serve as a source of inoculum, and they are often more susceptible to diseases and pests than younger leaves. Farmers who grow cucumbers in high tunnels primarily use two pruning/trellising systems: a mesh trellis with no or relatively limited pruning, or trellis to a single leader and prunes suckers. In our preliminary study, we used an intensive leaf pruning system in which we trellised the plant to a single leader and pruned not only suckers, but also older leaves. We pruned the leaves weekly as the plant was actively growing, leaving only 10-15 leaves for each plant during the entire production season. Using this system, we successfully suppressed powdery mildew and two-spotted spider mites without the need to spray pesticide. Although our results are promising, since we removed a large number of leaves that were green and still actively contributing photosynthesis, the intensive leaf pruning system could potentially negatively affect yield. Moreover, this approach required an extensive commitment of labor. A thorough evaluation of the intensive leaf pruning system, taking into considerations of pest control, yield and labor requirement is needed.

Our long-term goal in this multi-disciplinary project is to establish reproducible conditions that allow increased crop diversification and enhanced sustainability of high tunnel production systems. Our overall objective in this application is to identify alternative crops that can be successfully and profitably grown in high tunnels, and the production practices required to achieve these goals, with a primary focus on seedless cucumbers. The project is timely and important because it addresses one of the more important issues in high tunnel production systems, namely the need for crop diversification. In the past years, SARE has funded multiple projects related to the use of high tunnels. Among the projects focusing on vegetables, 12 were for tomatoes, eight for winter greens, one for peppers and one for melons. It is of considerable importance to expand the list of crops to encompass cucumbers, one of the most promising high tunnel crops.

Cooperators

Click linked name(s) to expand/collapse or show everyone's info
  • Bud Vogt
  • Jim Baughman
  • Candace Minster
  • Becky Brubaker
  • John Raber
  • Steve Willis
  • Daniel Garcia
  • Dan Perkins
  • Elaine Dougherty
  • Bronwyn Aly (Educator)
  • Andrea Liceaga (Researcher)
  • Cankui Zhang (Researcher)
  • Nash Bruce
  • Frank Burson
  • Brittany Denney
  • Dan Egel (Researcher)
  • Laura Ingwell (Researcher)
  • Liz Maynard (Researcher)
  • Ariana Torres (Researcher)
  • John Jamerson

Research

Hypothesis:

Our central hypothesis in this application is that through careful variety selection, well-designed cultural practices, and using grafting techniques, seedless cucumbers can be a high-value crop for high tunnel production.

Materials and methods:

Objective #1:

High tunnel seedless cucumber variety evaluations including 16 cultivars in 4 cucumber types were conducted in 2018 Spring at three locations: Southwest Purdue Agricultural Center in Vincennes, IN (SWPAC; USDA Hardiness Zone 6), Pinney Purdue Agricultural Center in Wanatah, IN (PPAC; USDA Hardiness Zone 5), and Dixon Springs Agricultural Center in Simpson, IL (DSAC; USDA Hardiness Zone 5). Cucumbers were grown in soils under conventional production systems at SWPAC and PPAC, and in a hydroponic system at the DSAC. Cucumber yield, growth characteristics, disease resistance and quality parameters were evaluated. A high tunnel prunning trial comparing one-leader system and mesh trellis system were conducted in 2018 and 2019 Spring at SWPAC. Two cultivars were used for the trial. 

Cucumber grafting trials have been conducted at the SWPAC in 2017 - 2019 seasons. Rootstocks of Cucurbita moschataCucurbita maxima × C. moschata, Cucurbita fixifolia and Cucumis sativus were evaluated for grafting three cucumber cultivars. Season extension potential, yield benefit and disease resistance were evaluated. Cucumber sensory analyses for grafted and non-grafted cucumber fruit were conducted at Purdue food sensory lab in 2018 and 2019.

Trials to evaluate relative cucumber beetle damage and bacterial wilt susceptibility were conducted at SWAPC in 2018, at Meigs Purdue Ag Center in 2019, and at on-farm trials in 2019.

Objective #2: 

Cost of producing grafted cucumber plants was estimated. Partial budget and sensitivity analyses for incorporating grafting technique into high tunnel cucumber production system were conducted.

We interviewed farmers about the economic outcome of growing cucumbers in high tunnels 

Objective #3: 

Farmers’ inputs were incorporated into initial planning of research activities. For example, we consulted farmer collaborators for popular cultivars, typical planning date, pruning & trellising method etc. During the project implementation period, a total of 22 on-farm trials were conducted from 2018 to 2020. Grafted plants were produced at the SWPAC and distributed to farmer collaborators. Farmers collected data and returned results to the project team. Farmers were compensated for the time involved in participating the project. Summary reports were produced and shared with farmer collaborators at the end of each year (2019, 2020). Two farmer collaborators’ meetings were conducted, one was held at Indiana Small Farm Conference in March 2019, one was held virtually in Nov. 2020. Farmers shared their observations on growing grafted and non-grafted cucumbers, what they have learned by participating in the project, and discussed production challenges. A survey was distributed among farmer collaborators following the Nov. 2020 meeting.

Information was distributed to a broader audience through presentations at grower and academic meetings; extension and peer-reviewed journal articles, field days, demonstrations, videos etc. A detailed list of the project activities is listed under Educational & Outreach Activities.

Research results and discussion:

Objective #1
Specific research results and discussion can be found in four peer-reviewed journal articles:
1. Guan, W.T. Maynard, B. Aly, J. Zakes, D.S. Egel and L.L. Ingwell. 2019. Parthenocarpic cucumber cultivar evaluation in high-tunnel production. HortTechnology. 29:634-642.
2. Guan, W., D. Egel, L. Sutterer, A. Plummer. 2018. Early season production of grafted seedless cucumbers in high tunnels. HortTechnology. 28:74-79.
3. Guan, W., D. Nowaskie, and D. Haseman. 2020. Rootstock evaluation for grafted cucumbers grown in high tunnels: yield and plant growth. HortScience. 55:914-919.
4. Egel, Dan, Guan, T. Creswell, and J. Bonkowski. 2020. First Report of Macrophomina phaseolina causing charcoal rot of cucumber in Indiana. Plant Disease. Vol. 104. https://doi.org/10.1094/PDIS-11-19-2421-PDN

Objective #2:
The results of the economic analyses was published as a peer-reviewed journal article:
Rodriguez Izaba, O., W. Guan and A.P. Torres. 2021. Economic analysis of growing grafted cucumber plants for high tunnel production. HortTechnology. 31:181-187.

Objective #3:
A total of 13 farmers who participated on-farm trials, and participated in farmer collaborators' meetings. Those farmers directly benefited from the project. Field days conducted in IN and IL highlighted this project and introduced the information to a broader audience. The project information was delivered to farmers, researchers, extension professionals, and industry stakeholders at farmers’ conferences in IN, IL, MI, OH, MN and IA, as well as at national professional conference. The project leads to a comprehensive High Tunnel Cucumber Production Guide, which includes information on cultivar selection, pruning and trellising systems, insect and mite pest management, disease management, plant physiological disorders, and grafting techniques that are tailored to cucumber production in high tunnels. The production guide has about 1200 downloads within five months of its release. An extension bulletin (HO-328-W) and a YouTube video explaining cucumber grafting technique were developed. The video has about 30,000 views since its release in Feb. 2019.

Research conclusions:

Our results indicated that farmers should select seedless cucumber cultivars based on consumer preference, yield potential, disease resistance, and insect pest tolerance. Pruning and trellising systems should be adjusted according to cultivars, available labor, and the anticipated harvest duration. Recommendations for cultivar selection, pest management,  and pruning/trellising systems are developed according to specific production and marketing conditions of each farm.

Our research in using grafting technology in high tunnel cucumber production indicated that grafting is an effective approach to increase early-season cucumber production; hybrid squash rootstock is the most suitable rootstock for the high tunnel cucumber production system; sensory properties of cucumber fruit were not affected by grafting. Economic analyses suggested that grafting can be an economically feasible tool for high tunnel seedless cucumber production. However, the study also revealed that grafting on-site may not be feasible for all diversified and small farmers. Economic models based on on-site producing grafted transplants vs. purchasing grafted transplants should be investigated. The on-farm trials in the current project revealed that grafted cucumbers may perform poorly in soils with high pH or high salinity. Future research is warranted to confirm the observation and select rootstocks to overcome the challenge.

A new cucumber disease charcoal rot that typically occurs in the tropical areas was found on cucumbers in Indiana for the first time. A first report was generated out of this finding. This project identified two-spotted spider mites as one of the most important pests in high tunnel cucumber production and generated preliminary data showing varietal differences toward two-spotted spider mites susceptibility. These findings lead to another SARE grant LNC20-438.

Participation Summary
13 Farmers participating in research

Education

Educational approach:

Educational approach used in the project include: 

Face-to-face communication with farmers

On-farm trials

Field days

Workshop and demonstrations

Presentations at growers' meetings

Extension bulletins

Newsletter articles

Peer-reviewed journal articles. 

Project Activities

2017 Southwest Purdue Agricultural Center Field Day
2018 High Tunnel Tour at Southwest Purdue Agricultural Center
2018 Dixon Springs Agricultural Center Twilight Meeting
White Violet Center for Eco-Justice natural day and cucumber grafting project radio show
IN Parke County Vegetable Growers Meeting
2019 Illiana Vegetable Growers Symposium
Present and demonstrate cucumber grafting at 2019 Illinois summer twilight meeting
Presentation at 2019 Indiana Hort Congress
Vegetable grafting workshop in 2019 at Southeast Indiana Vegetable Growers Meeting
Demonstration and presentation at 2019 Indiana Small Farm Conference
2019 Southwest Purdue Agricultural Center Field Day
2019 Illinois Summer Twilight Meeting at Dixon Springs Ag Center
Presentation at 2021 Mid-Atlantic Fruit and Vegetable Convention
Presentation at 2021 Minnesota Fruit Vegetable Growers Convention
Presentation at 2020 Great Lakes Fruit, Vegetable & Farm Market Expo
Presentation at 2020 Illinois Specialty Crop Growers Conference
Presentation at 2020 Indiana Small Farm Conference
Presentation at 2021 Iowa High Tunnel Short Course

Educational & Outreach Activities

50 Consultations
3 Curricula, factsheets or educational tools
5 Journal articles
22 On-farm demonstrations
16 Published press articles, newsletters
15 Webinars / talks / presentations
9 Workshop field days

Participation Summary:

817 Farmers
80 Ag professionals participated
Education/outreach description:

Journal articles

  1. Rodriguez Izaba, O., W. Guan and A.P. Torres. 2021. Economic analysis of growing grafted cucumber plants for high tunnel production. HortTechnology. DOI: https://doi.org/10.21273/HORTTECH04747-20
  2. Guan, W., D. Nowaskie and D. Haseman. 2020. Rootstock evaluation for grafted cucumbers grown in high tunnels: yield and plant growth. HortScience. 55:914-919. 
  3. Guan, W., E.T. Maynard, B. Aly, J. Zakes, D.S. Egel and L.L. Ingwell. 2019. Parthenocarpic cucumber cultivar evaluation in high-tunnel production. HortTechnology. 29:634-642.
  4. Guan, W., D. Egel, L. Sutterer, A. Plummer. 2018. Early season production of grafted seedless cucumbers in high tunnels. HortTechnology. 28:74-79.
  5. Egel, Dan, W. Guan, T. Creswell, and J. Bonkowski. 2020. First Report of Macrophomina phaseolina causing charcoal rot of cucumber in Indiana. Plant Disease. Vol. 104. https://doi.org/10.1094/PDIS-11-19-2421-PDN

Curricula, factsheets, or educational tools

  1. Guan, W. L. Ingwell, and D. Egel. 2020. High tunnel cucumber production guide. Purdue Extension. ID-521-W.
  2. Guan, W. 2019. How to splice graft cucumber plants. Purdue Extension. HO-328-W.
  3. Guan, W. 2019. How to splice graft cucumbers. Purdue University Extension. https://www.youtube.com/watch?v=z-tXoobiMnY&t=2s 13,525 views as of Aug. 2020

Press article and newsletters

Purdue Extension newsletter Vegetable Crops Hotline has a total of 641 subscriptions.

  1. Guan, W. 2018. Grafting cucumbers in high tunnels can solve the cold factor. American Vegetable Grower. https://www.growingproduce.com/vegetables/cucurbits/grafting-cucumbers-high-tunnels-can-solve-cold-factor/
  2. Guan, W. 2020. Summary of 2020 on-farm grafted cucumber trials. Vegetable Crops Hotline https://vegcropshotline.org/summary-of-2020-on-farm-grafted-cucumber-trials/
  3. Guan, W. 2020. Summary of 2019 on-farm grafted cucumber trials. Vegetable Crops Hotline https://vegcropshotline.org/summary-of-2019-on-farm-grafted-cucumber-trials/
  4. Guan, W. 2020. High tunnel cucumber production guide. Vegetable Crops Hotline https://vegcropshotline.org/article/high-tunnel-cucumber-production-guide/
  5. Guan, W. 2020. Learn how to graft tomato and cucumber plants. Vegetable Crops Hotline https://vegcropshotline.org/article/learn-how-to-graft-tomato-and-cucumber-plants/
  6. Guan, W. 2020. Call for growers’ participation of grafted cucumber research. Vegetable Crops Hotline https://vegcropshotline.org/article/call-for-growers-participation-of-a-grafted-cucumber-research/
  7. Guan, W. 2019. Variety selection is important for managing cucumber powdery mildew in high tunnels. Vegetable Crops Hotline https://vegcropshotline.org/article/variety-selection-is-important-for-managing-cucumber-powdery-mildew-in-high-tunnels/
  8. Guan, W. and L. Ingwell. 2019. Watch for two-spotted spider mites on high tunnel cucumbers. Vegetable Crops Hotline https://vegcropshotline.org/article/watch-for-two-spotted-spider-mites-on-high-tunnel-cucumbers/
  9. Guan, W. 2019. Learn how to graft tomato and cucumber plants. Vegetable Crops Hotline https://vegcropshotline.org/article/learn-how-to-graft-cucumber-and-tomato-plants/
  10. Guan, W. 2018. Are you interested in participating in a grafted cucumber study. Vegetable Crops Hotline https://vegcropshotline.org/article/are-you-interested-in-participating-the-grafted-cucumber-study/
  11. Guan, W. 2018. Growing grafted cucumbers for early season production in protected cultural systems – Lessons learned from on-farm trials. Vegetable Crops Hotline https://vegcropshotline.org/article/growing-grafted-cucumbers-for-early-season-production-in-protected-cultural-systems-lessons-learned-from-on-farm-trials/
  12. Egel, D. 2018. New disease report-charcoal rot of cucumber. Vegetable Crops Hotline https://vegcropshotline.org/article/new-disease-report-charcoal-rot-of-cucumber/
  13. Guan, W. D. Egel and L. Ingwell. 2018. Bacterial wilt of cucumbers grown in a high tunnel. Vegetable Crops Hotline https://vegcropshotline.org/article/bacterial-wilt-of-cucumbers-grown-in-a-high-tunnel/
  14. Guan, W. 2018. Check soil temperatures before planting cucumbers in a high tunnel. Vegetable Crops Hotline https://vegcropshotline.org/article/check-soil-temperatures-before-planting-cucumbers-in-a-high-tunnel/
  15. Guan, W. 2018. What you need to know about cucumber varieties in high tunnel production. Vegetable Crops Hotline https://vegcropshotline.org/article/what-you-need-to-know-about-cucumber-varieties-for-high-tunnel-production/
  16. Guan, W. 2017. Are you interested in growing greenhouse type cucumbers in high tunnels, and targeting for early season production https://vegcropshotline.org/article/are-you-interested-in-growing-greenhouse-type-cucumbers-in-high-tunnels-and-targeting-for-early-season-production/

On-farm demonstration

Collaborate farms, year, location and production system

Collaborate farms

Year

Location

Production system

Freedom Valley Farm

2018, 2019, 2020

Freedom, IN

Unheated high tunnel

White Violet Center

2018

Terre Haute, IN

Unheated high tunnel

Bud’s Farm Market

2018

Evansville, IN

Heated greenhouse

Weathered Plow Farm and Greenhouses

2018, 2019

Camden, IN

Unheated high tunnel and Heated greenhouse

S&E Produce & Flowers

2018

Greenwood, IN

Unheated high tunnel

Perkins’ Good Early Farm

2018, 2020

De Motte, IN

Unheated high tunnel

JR Greenhouse

2018

Odon, IN

Heated greenhouse

Garcia’s Garden

2018

Indianapolis, IN

Unheated high tunnel

Just Farmin’

2018, 2019. 2020

Middletown, OH

Unheated high tunnel

Burson Family Farm

2019, 2020

Evansville, IN

Unheated high tunnel

Five Hands Farm

2019, 2020

Lowell, IN

Unheated high tunnel

Denney Farm

2019, 2020

Silver Lake, IN

Heated greenhouse

Legacy taste of the garden

2020

Princeton, IN 

unheated high tunnel

Presentations

  1. 2021 Iowa High Tunnel Short Course. Growing and managing cucumbers in high tunnels. Ames, IA. Nov. 8 2021. (Attendance: 120)
  2. Purdue Extension Vegetable Farming Webinar Series. High tunnel cucumber production tips. Virtual 10 Feb. 2021.
  3. Mid-Atlantic Fruit and Vegetable Convention. Opportunities for growing grafted cucumbers in high tunnels. Virtual. Feb. 11 2021.
  4. 2021 Minnesota Fruit Vegetable Growers Convention. Grafted plants in cucumber, watermelon & melon production. Virtual. Jan. 2021. (Attendance: 40)
  5. Great Lakes Fruit, Vegetable & Farm Market Expo. Using Grafted Plants in Cucumber and Melon Production. Virtual. Dec. 2020. (Attendance: 45)
  6. Indiana Small Farm Conference. Cucumber rootstock evaluation. Danville, IN. Mar. 2020. (Attendance: 36)
  7. Indiana Horticulture Conference & Expo. Grafted cucumbers for early season production in high tunnels. Indianapolis, IN. Feb. 2020. (Attendance: 15)
  8. Indiana Horticulture Conference & Expo. High tunnel cucumber production. Indianapolis, IN. Feb. 2020. (Attendance: 10)
  9. Illinois Specialty Crop Growers Conference. High tunnel cucumber production. Springfield, IL. Jan. 2020. (Attendance: 35)
  10. 2019 Indiana Small Farm Conference. Cucumber grafting. Danville, IN. Mar. 2019. (Attendance: 25)
  11. Indiana Hort Congress. Seedless cucumber: another high-value crop for high tunnels and what grafting could do. Indianapolis, IN, Feb. 2019. (Attendance: 34)
  12. Illiana Vegetable Growers Symposium. Cucumber production in high tunnels. Schereville, IN. Jan. 2019. (Attendance: 73)
  13. Parke County Vegetable Growers Meeting. Cucumber production in high tunnels. Marshall, IN. Dec. 2018. (Attendance: 73)
  14. 2018 Illinois Summer Twilight Series: Dixon Springs Ag Center. High tunnel cucumber production. Simpson, IL. May 2018. (Attendance: 32)
  15. Indiana Hort Congress. High tunnel cucumber varieties. Indianapolis, IN, Feb. 2018.

Field days/workshop

  1. 2019 Southwest Purdue Agricultural Center Field day. June 27, 2019. Vincennes, IN. Cucumber rootstock evaluation and cucumber trellis and pruning system were demonstrated at the field day (Attendance 72)
  2. 2018 Southwest Purdue Agricultural Center High Tunnel Tour. June 13, 2019. Vincennes, IN. Seedless cucumber cultivar performance and taste test, cucumber pruning system, and striped cucumber beetle management were highlighted at the field day (Attendance 25).
  3. 2017 Southwest Purdue Agricultural Center Field day. June 26, 2017. Vincennes, IN. High tunnel cucumber production was demonstrated at the field day (Attendance 70).
  4. Illinois Summer Twilight Meeting. June 2019. Dixon Springs Agriculture Center, Simpson, IL. Cucumber grafting and rootstock evaluation were demonstrated at the field day (Attendance around 50).
  5. Illinois Summer Twilight Series: Dixon Springs Ag Center. May 2018. Dixon Springs Agriculture Center, Simpson, IL. Cucumber cultivar evaluation and taste test was conducted at the field day. (Attendance around 32)\
  6. Southeast Indiana Vegetable Growers Meeting. Vegetable grafting workshop. New Albany, IN. Mar. 2019. (Attendance: 30)
  7. Lake County Vegetable Growers Meeting. Vegetable grafting workshop. Crown Point, IN, May 2018.
  8. 2019 Indiana Small Farm Conference. Cucumber grafting workshop. Danville, IN. Mar. 2019.
  9. 2020 Indiana Horticulture Conference & Expo. Cucumber grafting workshop. Indianapolis, IN. Feb. 2020.

 

Learning Outcomes

142 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
18 Agricultural service providers reported changes in knowledge, skills, and/or attitudes as a result of their participation
Key areas taught:
  • High tunnel cucumber variety selection
  • cucumber grafting technique and benefit
  • importance of soil temperatures in cucumber production
  • Pruning and trellising systems of growing cucumbers in high tunnels
  • High tunnel cucumber disease management
  • High tunnel cucumber insect pest management

Project Outcomes

4 Farmers changed or adopted a practice
Key practices changed:
  • Adopt cucumber grafting technique to enhance early-season production

  • Improve high tunnel cucumber pest management

  • Improve pruning trellising system

  • High tunnel cucumber variety selection

1 Grant applied for that built upon this project
1 Grant received that built upon this project
20 New working collaborations
Success stories:

The project has two major influences on vegetable farmers and the industry.

One of the influences is introduced grafting technique in cucumber production in high tunnels. Prior to this project, few farmers are heard about cucumber grafting and seldom aware that grafting can improve plants tolerance to low temperatures. This project introduced grafting technique in high tunnel cucumber production; and identified benefits of using this technique, which is to improve plants cold tolerance, and to enhance early-season cucumber production. The project also helped farmers better understand the importance of soil temperatures to vegetable growth and production.

A total of 13 farmers participated 22 on-farm trials in three years. Among them, at least 6 farmers saw benefits of using grafted plants. Here are quotes from farmers describing benefits of using grafted plants.

'We are first market of cucumbers by three weeks. It makes a difference, sales-wise. It gets us ahead of the game quickly. It paid off very well. We are ready to grow all grafted.'--- a high tunnel farmer from west OH. Nov. 2020. 

'The benefit is early market, weeks before anybody else get into the market, sell it with a premium price. Typically later on in the season, we will lower our price. When the latter on, other farmers start to bring to the market. We do get some extra boost as well.' --- a high tunnel farmer from central IN. Nov. 2020. 

Four farmers suggested they would incorporate grafting practice in their production and one farmers reported above 90% survival rate by grafting cucumbers on their own.

The project has influenced business of a nursery that is specialized in producing grafted vegetable transplants. One of their representatives participated the farmer collaborators’ meeting in Nov. 2020. The working relationship between farmers and the nursery was established. The nursery expressed interest in working with small farmers and to expand business in selling grafted cucumber plants after the meeting.

The second major influence of the project is to provide farmers and agricultural professionals technical support of growing cucumbers in high tunnels. These technique support include recommendations on variety selection; cultural practices; disease and insect pest management. Farmers in six states (IN, IL, OH, MI, MN, IA) benefited from these recommendations. The High Tunnel Cucumber Production Guide was a National Award Winner by American Society for Horticultural Science, Extension Division. The guide achieved about 1200 downloads within 5 months of its release. It is highly valued by farmers and extension professionals nationally. Here is a quote from an agricultural professional about this guide.

'I really like the layout you used, with lots of pictures.  I like how simple and direct to the point the language is, too, it feels very grower friendly and attuned to shortened attention spans, while still giving enough info to troubleshoot the common problems.  I'm excited to share the resource!' --- a vegetable specialist in Cornell. Nov. 2020. 

Recommendations:

The project illustrated benefits of incorporating grafting technique in high tunnel cucumber production. It also identified challenges of using this technique. We noticed from on-farm trials that grafted plants may perform poorly if soils in high tunnels had abnormally high soil pH or soil salinity. It is critical to confirm the observation in future research and select rootstocks to overcome the obstacles. Another challenge prevent high tunnel farmers from using grafting technique in cucumber production is the availability of grafted cucumber transplants. Successfully producing grafted cucumber transplants need specific environmental conditions, training, and time investment that can be hard to achieve by small farmers. In the survey among participate farmers of this project, 67% respondents indicated that they prefer grafting the plants on-site while 33% suggested they prefer purchasing grafted cucumber transplants. The current grafting nurseries that specialized in producing grafted cucurbit plants are primarily focusing on producing grafted watermelon transplants for large-scale watermelon production. Future projects that aim to assist developing nursery businesses that specified in supplying grafted cucumber plants for small-scale high tunnels farmers would facilitate the adaption of the grafting practice.

The project increased farmers awareness of the importance of soil temperatures on growing cucumbers in early seasons and identified grafting practice is one way to overcome the challenge. Another approach farmers may use to overcome the soil temperature challenge is to heat the soil. Future research should be conducted to better understand pros and cons of each of the practices and explore the economic outcomes of using these practices.

Information Products

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.