Improving Success with Soil-less Rooting Media

Researchers representing the USDA and six universities are spearheading an effort to improve both soil-less rooting media used in specialty crop and transplant production and peoples’ success using soil-less media. Their research focuses on grower concerns and their extension/outreach will include a North American Soilless Substrate Summit. The team’s work is supported by the USDA Specialty Crop Research Initiative  (Grant # 2020-02629). Learn more about it by contacting Dr. James Owen in Wooster, OH (jim.owen@usda.gov; 757-374-8153) or Dr. Jeb Fields (jsfields@agcenter.lsu.edu; 985-543-4125). Just as important, help steer the team’s research by completing a 5-minute survey at https://bit.ly/2ZLNIkn.

Grafting, In-row Spacing, and Seasonal Nitrogen Application Rate Effects on Watermelon Yield and Quality

Growers, consultants, seed company representatives, and others have questions about watermelon management protocols, especially when grafted plants are used. The three panels below provide background on and summarize preliminary findings from two experiments on this topic completed in Wooster in 2020.

Please contact me at kleinhenz.1@osu.edu or 330.263.3810 for more information.

Optimizing Plant Spacing (Population) and Seasonal Nitrogen Rates in Grafted Watermelon Production

Data collection on fruit taken from two “grafted watermelon” experiments being completed at the OARDC in Wooster,OH has started. These experiments were outlined in VegNet posts on June 6 and July 11 and they are described in the image below, too.

Harvest 1 occurred on 8/19/20 with ‘Jade Star’ fruit harvest and analysis. The first harvest of ‘Fascination’ will be the week of 8/24 and a second harvest of each variety from both experiments is also planned. We assess the maturity of each fruit and its readiness for harvest using these criteria: a) yellow belly, b) dry vine tendril, c) developing longitudinal ridges, and d) white stripes brightening and widening (‘Fascination’). Occasionally, fruit weighing less than 8 lb meet one or more of these criteria, so they are harvested and photographed along with all other fruit from the same plot. Fruit weighing less than 8 lb are later separated from the group of fruit weighing more than 8 lb (marketable). In all pictures below, fruit are shown on a blue tarp slightly larger than 7 ft wide x 4 ft tall.

Pictures below are representative of what was observed in replicates 1-3 but conclusions should not be drawn from them. Data from Harvest 2 are needed to complete the picture and all data from 2020 must be analyzed along with data from previous years of the research (2018, 2019). On 8/19/20, in the “density” study, we observed that all four plots containing grafted plants produced a total of 12 fewer fruit than the four plots containing grafted plants at an in-row plant spacing of four feet. However, the situation was reversed at an in-row plant spacing of five feet since the four plots containing grafted plants produced a total of thirty-five more fruit than the four plots containing ungrafted plants at the same spacing.

The last planned fertilizer application (fertigation) in the “fertility” study was completed on 8/21/20. Two days before, the number of fruit taken from all twelve plots containing grafted plants was greater than the number of fruit taken from the twelve plots with ungrafted plants, regardless of seasonal nitrogen (N) rate. The difference in fruit number was greatest, moderate, and least at 75%, 100%, and 50% of the normal N rate, respectively. The pictures below are an example of the difference in fruit number at the standard N rate developed for watermelon production using ungrafted plants.

The experiments are being completed with USDA-SCRI program support and we look forward to sharing the results when the work is complete. In the meantime, please contact us (kleinhenz.1@osu.edu; 330.263.3810) for more information.

“Effects of the COVID-19 Outbreak on Specialty Crop Operations and Markets”

 

 

August 5, 2020

Dear Specialty Crop Grower,

I am writing to you today to request your assistance with a study about the effects of the COVID-19 outbreak on specialty crop operations and markets. Our purpose is to examine how different groups of stakeholders within specialty crops have been affected, and how different value chain channels were disrupted. For this study specialty crops are vegetables, potatoes, melons, fruit, nuts, berries, flowers, bedding crops, nursery crops, food crops grown under protection, propagative materials, and mushroom crops. Ultimately, the intentions of this study are to generate new knowledge that will guide future extension outreach activities, and to quantify the impact in terms of production losses and reduction in sales. This project is being led by researchers in the College of Food, Agricultural, and Environmental Sciences at Ohio State University with internal support.

We realize that your time is valuable and hope you consider participating in this study. To show our appreciation we offer a $10 e-gift card to the first 200 eligible participants. Eligible participants are owners and/or leading operators of specialty crop businesses within the state of Ohio, who choose to inform name and email address at the end of the questionnaire. Participating in this study means sharing your personal experience while playing the role of a leading agribusiness owner/operator. The questionnaire is available through OSU Qualtrics by clicking this link. Qualtrics is a world-class service provider that offers a secure line for internet-based surveys. Numerous universities across the country use Qualtrics to distribute surveys and collect valuable research data. Ohio State, Cornell, Stanford, Notre Dame, Purdue, and University of Illinois are some of the universities using Qualtrics.

The questionnaire is also available in paper format. If you prefer to participate using a paper-based questionnaire, do not hesitate to contact me and I will send you a hard copy of the questionnaire. The envelope will include a consent form with additional details about this study, the questionnaire, and a prepaid return envelope. Please make sure to sign and return the consent form along with the filled questionnaire if you decide to take part in this study. You can contact me by email at signorini.2@osu.edu, by phone at (614) 292-3871, or by postal mail at 2001 Fyffe Rd., 225 Howlett Hall, Columbus, OH, 43210. If you have questions about this study, I will be most happy to answer.

Yours sincerely,
Guil Signorini, PhD – Assistant Professor / Research Scientist Department of Horticulture and Crop Science College of Food, Agricultural, and Environmental Sciences, Ohio State University

 

You may also contact Gigi Neal, OSU Ag & Natural Resources Extension Educator, Clermont County at neal.331@osu.edu or 513-732-7070 or Brad Bergefurd, OSU Extension Horticulture Specialist, OSU South Centers at bergefurd.1@osu.edu or 740-289-3727.

Rotation Crops in High Tunnel Production

Many growers establish cash and non-cash rotation or cover crops each main season with the percentage of land in cash and non-cash crops varying farm to farm and year to year. Non-cash rotation crops are established to help maintain or improve soil health and nutrient levels, suppress weed growth, break pest and disease cycles, and provide other benefits. Despite these benefits, typically, high tunnel vegetable growers can be understandably reluctant to devote high tunnel space to non-cash crops in summer (main season). Perhaps as a partial consequence, soil health challenges (e.g., declines in organic matter and increases in nutrient imbalances, salt accumulation, compaction, and disease and pest pressure) are increasing in high tunnel soils. Anecdotal reports mention declines in crop yield and/or quality and increases in costs to maintain productivity. It is reasonable to expect that these trends could be be slowed or reversed through the consistent use of non-vegetable rotation crops in high tunnel production much like they have in open field production. However, few conclusive high tunnel-based experiments have been completed on farms or research stations.

This situation was not necessarily front of mind when the VPSL established cowpea, pearl millet, and sorghum sudangrass in many of its high tunnels at the OARDC in Wooster in early summer. Rather, the decision was primarily pandemic-related as vegetable experiments planned for the tunnels were suspended. That said, a summer including non-cash rotation crops is providing us with the opportunity to observe and learn about them and their potential value going forward. Currently, we consider cowpea, pearl millet, and sorghum sudangrass as just three of many potentially useful ‘alternative’ high tunnel crops for main season plantings, regardless of whether their use is planned or unplanned. The pictures below are examples of what we have observed to date. Please contact us (kleinhenz.1@osu.edu; 330.263.3810) if you would like to discuss the plantings or the “high tunnel rotation” question further.

Grafting, In-row Spacing, and Total Seasonal Nitrogen Effects on Watermelon Yield and Quality

Growers, seed, grafted plant, and fertilizer suppliers, extension-research personnel, and others are interested in identifying if, where, and how grafted plants may fit in vegetable production toolboxes. Those questions can be answered reliably only after the performance of grafted plants is documented under a range of management schemes because it is possible that standard production practices may need to be altered to account for the influence of rootstocks. Plant spacing (i.e., population density per acre) and fertilizer application rates (e.g., total seasonal nitrogen applied) are two variables likely to influence (grafted) plant performance; therefore, they have many peoples’ attention, including ours.

With USDA-SCRI program support, we began studying these variables at a preliminary level in 2018 and more thoroughly in 2019. Experiments started in 2019 are being repeated in 2020.

Data collection begins with tracking crop development and concludes with laboratory analyses of fruit quality. The experiments provide an opportunity to analyze fruit yield and quality as influenced by grafting, scion, spacing, and N level. In 2019, soilborne disease did not appear to be a factor and grand mean total cumulative fruit yield (ton/acre) values were: a) 32.5 (ungrafted ‘Fascination’), b) 25.0 (ungrafted ‘Jade Star’), c) 42.6 (grafted ‘Fascination’), and d) 47.7 (grafted ‘Jade Star’); these values include data for all density and N rate treatments. Analyzing data collected in both study years more thoroughly will provide a more reliable assessment of the influence of grafting, in-row spacing (4 or 5 ft), and total seasonal N application (100, 120, or 142 lb/acre) on watermelon fruit yield and quality.

Grafted Plants, Suppliers, and Experiments


Growers typically convert to using grafted plants (e.g., tomato, watermelon) primarily because they can be much more productive when specific soilborne diseases are present (and the correct rootstock is used). In addition, however, grafted plants are often more vigorous than ungrafted ones of the same scion (fruiting variety). Grafted plants may also use water, fertilizer, and other inputs more efficiently. Therefore, it is necessary to optimize cultural and fertility practices for grafted plant-based production. Two experiments will be completed in this 1+ acre parcel in 2020. One experiment tests alternative fertilizer rates and the second experiment tests in-row spacings (plant populations/acre). All grafted plants are supplied by Tri-Hishtil in Mills River, NC.

Tri-Hishtil (http://www.trihishtil.com/) is one among a constantly-lengthening list of commercial grafted plant suppliers. Others include Banner Greenhouses (https://www.bannergreenhouses.com/), Grafted Growers (https://graftedgrowers.com/), and Re-Divined (https://redivined.weebly.com/) in the eastern U.S. and others based in the west. Local suppliers are also operating in Ohio and some farmers are preparing their own grafted plants. Commercial suppliers continue to ramp-up their capacity to meet the needs of vegetable growers, regardless of the size, location, or type of their operation (field and/or high tunnel; conventional and/or organic). Also, grafted plant costs are increasingly competitive. Overall, access to grafted plants is strong and increasing and no longer a reason for being unable to test the performance of grafted plants on your farm. The Vegetable Production Systems Lab at OARDC can also assist, if needed; we teach people how to graft and, in 2021, we hope to resume preparing small numbers of plants by request.

One empty and three filled cells of a 128-cell tray holding grafted watermelon plants prepared by Tri-Hishtil. Note roots are visible on the surface as healthy white ‘threads’ with smaller root hairs near the tip, creating a bottle-brush appearance. Slotted cells (as shown at the bottom-left) contribute to this root condition and morphology.

Hand-grafted watermelon plants from Tri-Hishtil in Mills River, NC.
Plant at left is Jade Star and plant at right is Fascination, both grafted to Carnivor rootstock.
Clear and green clips show the location of the graft union and supports (white sticks) will be removed at planting (scheduled for 6/8/20).
Root systems are well-developed, stems are sturdy, and the plants pull easily. Roots are not spiraling, partly due to the larger size and special shape of the cells.
Clips can be removed at planting or allowed to be forced off naturally by stem growth.

Contact Matt Kleinhenz (330.263.3810; kleinhenz.1@osu.edu) and see updates at this blog for more information.

Last Call – 2 More Pumpkin or Squash Growers for On-Farm Mustard Biofumigation Trial

Interested in seeing if planting mustard cover crops prior to pumpkins or squash can reduce soil borne diseases and increase your yield? We are looking for 2 more growers preferably in the central or southern part of the state to put out a mustard cover crop (MCC) biofumigation trial to reduce soil borne disease pressure with the following guidelines and conditions. Deadline to sign up is March 19.

Growers requirements and general protocol:
-Growers must plant in field known to have a Plectosporium blight infestation. Growers with fields infested with Fusarium or Phytophthora will also be considered.

-Growers need to have equipment to seed the cover crop, chop (bush hog or flail), incorporate (rototill), pack the soil (culti-mulcher) and possibly seal the soil using a sprayer or irrigation system. These steps will be done in rapid succession so 3 tractors are ideally needed, each hooked to an implement. Don’t have 3 tractors? Maybe borrow one from a neighbor for a few hours?

-Growers will put out 4 strips of MCC and 4 strips without a MCC.

-Strip sizes will be up to 0.1A each for a maximum of 0.8A needed for the entire on-farm study.

-Growers will plant Caliente Rojo, currently the highest yielding glucosinolate mustard available.

OSU will provide:
-The Caliente Rojo seed, the fertilizer (urea + granular ammonium sulfate) and 1K seeds of the hybrid Solid Gold (Rupp).

-We will evaluate each grower site for disease incidence on foliage three times during the season, plus a harvest where mature fruit are weighed and graded for disease.

Study Timeline
-The MCC strip plots fertilizer will be disked into the soil prior to seeding to ensure high biomass production.

-The MCC planting date will be between March 30 and April 30 based on soil conditions and weather forecasts.

-Approximately 50-60 days later, the MCC will be at peak flowering and will be chopped, rototill incorporated into the soil and then packed using culti-mulcher. If irrigation is available, water will be applied to help seal the soil and create a better environment for biofumigation.

-Within 10-14 days of incorporation, Solid Gold pumpkins will be transplanted or direct seeded into those strips at roughly 4ft spacing between plants. Note that transplants are preferred at each site instead of direct seeding. Transplants will lead to an earlier harvest.

Plot Care
Each farm will follow their own standard weed, insect and disease control and fertility practices on the 8 strips. The fungicides used on the crop will need to be discussed ahead of time so we can limit the use of fungicides that might help control Plectosporium blight. These fungicides are Flint, Cabrio, Quadris, Inspire Super and Merivon.

Disease ratings of incidence on vines, foliage and fruit will be taken at 14-21 day intervals from vining until fruit maturity. Sections of all strips will be harvested and fruit will be weighed and graded for disease.

Sign up
If interested in participating in this project or have questions, please contact me at 937-484-1526 or jasinski.4@osu.edu by March 19.

If growers want to see a video detailing the steps and processes involved with planting MCC as a biofumigant, check out the work we did in 2019 at https://youtu.be/Taz-PhDphhA.

This project is being funded by the Ohio Vegetable and Small Fruit Research and Development Program and the IPM Program.

Pumpkin & Squash Growers Wanted for On-Farm Mustard Biofumigation Trial

Plectosporium blight on fruit and handle.

Plectosporium blight on petioles and leaf veins.

In 2019, research was conducted into the use of mustard cover crops as a biofumigant to reduce a specific soil borne disease in pumpkins, Plectosporium blight, also known as white speck or Microdochium. The signs of this disease start out as spindle shaped lesions on the petioles, vines and back of leaf veins potentially killing the plant. If the disease progress, it can infect the handles and turn immature and mature fruit white.

Although our trial in 2019 was planted in a Plectosporium infested field, very little disease developed due to the near drought like conditions at the research station in South Charleston. In wetter locations around Ohio this disease was seen last year and we still think there is potential for this cultural technique to reduce disease in pumpkin and squash fields. To accomplish this on a wider scale in 2020, we plan to replicate and expand our mustard cover crop (MCC) biofumigation study to include on-farm trials with growers.

We are looking to recruit 4-6 growers preferably in the central or southern part of the state to put out a mustard cover crop biofumigation trial to reduce soil borne disease pressure with the following guidelines and conditions.

Growers requirements and general protocol:
-Growers must plant in field known to have a Plectosporium blight infestation. Growers with fields infested with Fusarium or Phytophthora will also be considered.

Equipment needed to successfully manage a mustard cover crop.

-Growers need to have equipment to seed the cover crop, chop (bush hog or flail), incorporate (rototill), pack the soil (culti-mulcher) and possibly seal the soil using a sprayer or irrigation system. These steps will be done in rapid succession so 3-4 tractors are ideally needed, each hooked to an implement.

-Growers will put out 4 strips of MCC and 4 strips without a MCC.

-Strip sizes will be up to 0.1A for a maximum of 0.8A needed for the entire on-farm study.

-Growers will plant Caliente Rojo, currently the highest yielding glucosinolate mustard cover crop available.

OSU will provide:
-The MCC seed, the fertilizer (urea + granular ammonium sulfate) and 1K seeds of the pumpkin hybrid Solid Gold (Rupp).

-Also evaluate each grower site for disease incidence on foliage three times during the season, plus a harvest where mature fruit are weighed and graded for disease.

Study Timeline:
-The MCC strip plots fertilizer will be disked into the soil prior to seeding to ensure high biomass production.

-The MCC planting date will be between March 30 and April 30 based on soil conditions and weather forecasts.

Mustard cover crop at full bloom.

-Approximately 50-60 days later, the MCC will be at peak flowering and will be chopped, rototill incorporated into the soil and then packed using culti-mulcher. If irrigation is available, water will be applied to help seal the soil and create a better environment for biofumigation.

-Within 10-14 days of incorporation, Solid Gold pumpkins will be transplanted into those strips at roughly 4ft spacing between plants. Note that transplants are preferred at each site instead of direct seeding, but if this is not possible, we can discuss options. Transplants will lead to an earlier harvest.

Plot Care:
Each farm will follow their own standard weed, insect and disease control and fertility practices on the 8 strips. The fungicides used on the crop will need to be discussed ahead of time so we can limit the use of fungicides that might help control Plectosporium blight. These fungicides are Flint, Cabrio, Quadris, Inspire Super and Merivon.

Disease ratings of incidence on vines, foliage and fruit will be taken at 14-21 day intervals from vining until fruit maturity. Sections of all strips will be harvested and fruit will be weighed and graded for disease.

The Big Picture:
By expanding the number of sites for this research through on-farm trials, we expect to see the potential MCC may have to reduce the soil borne disease complex affecting cucurbits. By recruiting growers into this process at a small scale, we hope to gain their valuable feedback as to the feasibility and challenges of using MCC on their farm. If successful, growers will spread the news to other growers who might be willing to try MCC on their farm. In addition to the potential biofumigation benefit, growers will be enhancing their soil organic matter levels and provide premium although brief pollinator habitat during flowering.

If growers want to see a video detailing the steps and processes involved with planting MCC as a biofumigant, check out the work we did in 2019 at https://youtu.be/Taz-PhDphhA.

Sign up:
If interested in participating in this project or have questions, please contact me at 937-484-1526 or jasinski.4@osu.edu by March 14.

This project is being funded by the Ohio Vegetable and Small Fruit Research and Development Program and the IPM Program.

From New and Unusual to Common (or Maybe Not): The Dynamic World of Specialty Varieties

“Specialty” — as it applies to vegetable varieties – usually refers to ones differing in at least one noticeable way from the mainstream version of the crop preferred or expected by most buyers. That difference can be in size, shape, color, flavor, texture, and/or other characteristics. Oftentimes, specialty varieties are initially grown specifically to attract or meet the stated interest of buyers looking for “something different from what they can get everywhere else” and willing to pay higher prices for it. In a small number of cases, markets for specialty varieties increase to the point that the specialty designation or perception falls away, i.e., the variety is so widely grown that it resets what is considered normal or mainstream, but that process can require years to complete. The opposite can occur, too, as markets for individual specialty varieties can remain small and fade quickly. In any case, when grown and marketed well to a sufficiently large number of buyers, even if local, specialty variety production can be profitable. Well documented cases of specialty vegetable and variety production being significant for many growers on both coasts and within easy reach of urban areas in states between them fill the extension, research, and industry literature. Some growers are, more or less, always searching for the next unusual variety that will help set their farm apart.

A variety just being different is not enough to attract and maintain the interest of most buyers. The difference must be meaningful. In the well-chronicled case of ‘Honeynut’ squash (e.g., see https://www.bonappetit.com/story/honeynut-squash-history), the most meaningful difference may be size since ‘Honeynut’ is positioned as a mini-butternut. Its small size makes ‘Honeynut’ more versatile and appealing to buyers looking for the culinary/dietary benefits of butternut fruit but in a smaller package.

We included ‘Honeynut’ squash in two experiments in 2019, planting it in the same rows as ‘Metro PMR’. ‘Honeynut’ was used as the “spacer” between plots of ‘Metro PMR’, the actual focus of the experiments, both of which were managed organically. However, observing ‘Honeynut’ during the season and completing informal eating quality assessments, its appeal is clear. ‘Honeynut’ serves as a reminder of the benefit of considering alternative varieties, especially as the period for selecting varieties and ordering seed for 2020 gets underway.