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.

One Example of How Grafting May Benefit Pepper Growers

From a buyer’s point of view, many characteristics contribute to pepper fruit quality. Quickly and at all points along the chain from farm to plate, quality is assessed based on a lengthy list of fruit characteristics (e.g., size, shape, color, weight, wall thickness, taste, texture) and using one or more of the senses and/or various instruments and technologies. Although most consumers expect high-quality versions of individual types of peppers (e.g., bell, habanero) to have specific sets of characteristics, others look for “new” or “different” versions of familiar crops and are often willing to pay more for them. With that and other important production-related considerations in mind, research at The OSU-OARDC is evaluating the effects of physically hybridizing different types of pepper plants – i.e., using bell, habanero, and other types of pepper as rootstock and scion during grafting. Varieties of different types of pepper are known for their vigor, maturity, disease and abiotic stress tolerance, and fruit size, shape, color, texture, taste (including “hotness”), etc. As with all other vegetable crops that are routinely grafted (tomato, eggplant, watermelon, cucumber, cantaloupe), plants and fruit resulting from combinations of pepper varieties made through grafting are being tested to determine if they provide growers with advantages so far unavailable from standard variety development. Grafted plants within this group were prepared months ago and include bell and “hot” varieties as rootstock or scion. When healed, the grafted plants and their ungrafted comparison plants were placed in containers in an outside growing area and managed using standard approaches. On Sept. 21, the plants were moved into a greenhouse so that fruit development could proceed more reliably, given the date. Going forward, fruit they produce will be examined in the laboratory, including for their level of capsaicin and relative “hotness”, in a process led by Dr. Joe Scheerens. Grafted and ungrafted versions of tomato and watermelon plants and fruit they have produced are being studied in four other large-scale field experiments also now moving into their laboratory and data analysis stage. Reports from these and other experiments will be issued throughout the fall-winter but Matt Kleinhenz can be reached for more information in the meantime.

Harvests of Data Hopefully Increase Harvests of Money

Experiments planned in Fall-Winter 2018-2019 and initiated this spring at the OARDC in Wooster, OH are now yielding crop-based data. Additional experiments initiated this past week or to be initiated within several weeks will provide additional numbers of potential value to growers. Overall, these experiments are supported by: (a) the USDA-NIFA Specialty Crop Research Initiative (https://nifa.usda.gov/program/specialty-crop-research-initiative-scri), (b) the USDA-NIFA Organic Transitions Program (https://nifa.usda.gov/program/organic-agriculture-program), (c) the USDA-NIFA Potato Breeding Research support program (https://nifa.usda.gov/funding-opportunity/potato-breeding-research), (d) North-central SARE (https://www.northcentralsare.org/), and (e) companies. Along with our collaborators, through these experiments, we look to provide growers and other members of the industry with information they can use beginning immediately, especially when making decisions involving the use of grafted plants, microbe-containing crop biostimulants, reduced-tillage approaches, high tunnels, and/or new potato varieties. Ideally, this information will increase the yield of money on Ohio farms.

Two ongoing experiments will help identify the optimal growing practices when grafted watermelon plants are used. Grafted watermelon plants are showing high potential in- and outside Ohio. However, their wider use has been slowed by their higher cost and the fact that yields from them are not always higher than from standard ungrafted plants. Importantly, an increasing amount of evidence provided by researchers and farmers suggests that growing practices may have to be altered in order to get the best return on investment from grafted watermelon plants. Studies and farmer experience point to changes in plant density, and/or nutrient and/or irrigation management as possibly beneficial. This is reasonable given characteristics of some watermelon rootstocks. So, since 2018, like others, we have been asking if yield can be maintained or increased even as grafted plant density or fertilizer inputs are modified. These two experiments total twelve variety-fertility program and eight variety-plant density treatments. On 8/21/19, the VPSL and OARDC Farm Crew harvested 849 “Jade Star” watermelon fruit from the forty plots spanning roughly 0.7 acre (including pollenizer plants). The 849 fruit totaled 6.2 tons (11 over-filled pallet boxes) and averaged 255 lbs/plot (nine plants). “Fascination” fruit will be taken from the same experiments the week of 8/26, fruit quality will be evaluated in the lab, and the harvest-evaluation process will be repeated for the same experiments to capture total crop yield potential. At the same time, we will continue to focus on: (a) tomato experiments testing grafting, strip-tillage, and/or microbial inoculant effects on fruit yield and quality; (b) butternut squash, carrot (fall high tunnel), and spinach (fall high tunnel) experiments testing microbial inoculant effects on yield and quality; and (c) potato experiments completed in cooperation with breeders at USDA, the University of Maine, Cornell University, and North Carolina State University.

Lab to Field to Basket: Potato Research and Extension to Strengthen the “Chip Business”

Pounds upon pounds upon pounds of potato chips are consumed each day. Few give the hard work on the farm or science and teamwork required to bring good chips to market one thought. Here, though, is a brief summary of recent activity in Ohio and elsewhere designed to help growers and processors and all others who rely directly and indirectly on local-regional “chip business.”

The Big Picture. USDA (e.g., https://www.nass.usda.gov/Publications/Todays_Reports/reports/pots0918.pdf) and other information makes clear that potato production and processing remain important, enormously valuable industries throughout the U.S., Great Lakes, and, still, Ohio. Nearby on the ground evidence includes Lennard Agriculture (https://www.lennardag.com/) and impressive investments it and its cooperators have made in infrastructure (e.g., center pivot irrigation systems), expertise, research, and other assets in a four-county area of the Scioto River Valley, among other locations. Early, summertime harvests of large, high-quality crops suitable for use in chip-making are important to them. This activity maintains the strong tradition of supplying local-regional chipmakers … page 20 of the USDA report mentioned earlier shows that the U.S. contains approximately 89 chip-making plants with 15 (16% of the total) located within Michigan, Ohio, and West Virginia. Thankfully in this case, it appears that little has changed since 2008 (https://www.potatopro.com/news/2008/ohio-boasts-second-most-potato-chip-manufacturers-us) and before.

Potatoes used to make chips must meet strict specifications. Tuber shape, size, specific gravity, sugar/starch content, flesh color, natural or man-made damage, and other characteristics influence the chip-maker’s desire for the crop. Since these traits hinge on each combination of potato variety, crop management, and growing conditions, the pressure is on growers to optimize each combination. Improved varieties better able to thrive in various conditions are always needed. With important exceptions, potato varieties used in chip-making in the U.S are bred by teams at USDA and a small number of universities, including Michigan State Univ. (http://potatobg.css.msu.edu/). In 2019, led by Chris Long of MSUE (https://www.canr.msu.edu/people/christopher_long), plots of a total of fifteen experimental selections from MSU, USDA, Cornell Univ., and North Carolina State Univ. were planted alongside ones of “check” varieties in fields in Ohio coordinated by Lennard Agriculture. During Aug 13-16, the OSUE team including Chris Bruynis and Ross Meeker (https://ross.osu.edu/about/staff), Brad Bergefurd (https://scioto.osu.edu/about/staff), Mike Estadt (https://pickaway.osu.edu/about/staff), Will Hamman (https://pike.osu.edu/about/staff), and the VPSL (http://u.osu.edu/vegprolab/) harvested the plots and collected key data on the tubers. The VPSL has a long history of cooperating with potato breeders and others in developing improved varieties (e.g., see reports at http://u.osu.edu/vegprolab/technical-reports/).

Yield was measured first and it ranged from 1.3 to 2.6 pounds per foot of row across all selections and varieties (these values equate to 226 and 452 hundred-weight/acre, resp.). Tuber specific gravity (S.G.) using the weight in air, weight in water method and a hygrometer was measured next (see URL above). This method involves placing exactly eight pounds of tubers (air, at left) into a basket attached to an air-filled bulb and calibrated meter. The basket-bulb-meter unit is then placed in water (middle and right). It will sink to a depth roughly consistent with the tubers’ combined moisture and dry matter (especially sugar/starch) levels. Tubers high in S.G. are needed in chip-making; S.G. is influenced by variety, management (especially nutrient and irrigation), and other environmental factors. The S.G. of experimental selections … lines still being tested and not yet named … is always benchmarked against the specific gravity of well-known standard varieties.

Next, tubers were peeled and placed in cold water until chipped. Tuber flesh that has been damaged and exposed to air typically begins to oxidize and brown. Submersion in cold water slows the process. Commercial chip-makers and other potato processors remove potato skin using various methods often involving pressure and/or steam.

In commercial chip-making, peeled tubers are then sliced to product-specific thicknesses. Chip enthusiasts know that products vary in chip thickness, a variable that has multiple significant implications for the chip-maker and for research teams working on their behalf. Slice thickness influences fry time, oil-absorption, chip texture, and many other variables which influence the suitability of a variety for the specific product. As in our other potato research, here, we produced slices measuring 0.051 inches thick using a DeBuyer Kobra mandolin slicer.

Slices were then fried for 3.5 minutes using oil provided by a local chip-maker (Shearer’s Foods, Inc.) and a standard tabletop fryer (left). The target oil temperature was 350 deg F and the actual oil temperature was monitored throughout and allowed to reach the target between batches. Finally, the color of completed batches was scored against the industry-wide standard Color Chart developed by the Snack Food Association of America (sfa.org; below right). A rating of 1 (upper left of chart) is desired by most chip-makers. Many batches completed on 8/16/19 using tubers harvested in the Scioto River Valley area scored 1-3, a very promising result. Remaining tubers have been placed in cold storage and will be chipped again later, as one assessment of the rate at which each genotype converts starch to sugar when exposed to storage-like temperatures.

Land. Equipment. Good varieties and growing methods. Proper inputs. And, crop-friendly weather. These are just some of the resources needed for success on the farm. However, a great team is also essential … just as in research, extension, and other activities. In 2019, for the VPSL, like for other teams, data collection is ongoing. The potato evaluation outlined here will be followed by work with tomato, squash, watermelon, carrot, and other crops, with plots in fields and high tunnels and at OARDC and on commercial farms.

 

 

 

 

 

 

 

Making Up Lost Ground (actually, for Lost Plants or Leaves)

Reviewing the condition of various farm fields and research plots prompted me to revisit the process or phenomenon of yield compensation (also mentioned in VegNet June 30). Recently, I saw fields and plots showing missing plants and plants with leaves damaged by insect feeding, mechanical damage, and other causes.

For each crop, there is a plant population shown by research and/or experience to maximize yield potential under specific combinations of variety, planting date, irrigation and fertility program, and other factors. Similarly, yield potential is known to be greatest within target ranges of leaf area index (LAI). LAI is calculated as half the area of all leaves per unit area of ground. It is measured as the leaf area (e.g., square feet) per ground area (square feet) and unit-less. So, a plant, field, farm, or region with a LAI of 3 has enough leaf surface (one-sided) to cover an area three times larger than the area from which the leaves were collected. To calculate LAI, most researchers collect all leaves from above a known area of ground, scan the leaves to calculate their total area, then divide that area by the area from which the leaves were collected. Techniques involving cameras and smartphones are improving the opportunity for obtaining estimates of LAI in the field without removing leaves. Regardless, LAI values have long been used in different ways in agriculture, forestry, climatology, ecology, and other disciplines and industries.

Overall, yield compensation asks if yield will be reduced if plant populations or LAI values are less than the target. The answer is easy for some crops such as fresh market sweet corn; “yes”, since one less plant results in one less ear available for harvest. The answer is more complicated (and encouraging) for other crops able to “compensate” for a reduction in plant population and/or leaf area (LAI) under specific circumstances.

This picture taken at OARDC shows a young butternut squash planting. Based on in-row plant spacing, the image should contain thirty-four plants. However, four plants (12%) are missing outright and four others are noticeably weaker than all remaining ones. So, the absolute percent stand is 88% but, functionally, it may be as low as 76%. Will this planting have a yield equivalent to the yield at 100% of the target population? That is, will the remaining plants compensate for missing ones?

Work completed in 1998 and 1999 by a team of extension specialists in NY and PA gives some clues. Dr. Anu Rangarajan and her collaborators studied defoliation and plant loss effects on butternut squash yield (fruit number, size, and weight) and other variables. Stands ranging from 25 to 100 percent of target populations were created at different stages of growth. Likewise, stands were defoliated to simulate damage due to insect feeding, hail, or other issues. The team summarized its work in the July-September 2003 issue of the journal HortTechnology. Borrowing from that report, the team stated that reducing plant populations or leaf area reduced marketable yield, fruit number, and individual plant productivity (but not fruit carotene content). Damage occurring during fruit enlargement had a greater effect than damage occurring early in the season. Generally, yield was directly proportional to plant population. However, if plant population losses occurred when plants were in the rapid vegetative growth phase, remaining plants responded by increasing fruit number and weight per plant. Still, this compensation did not always provide yields equivalent to the original population. The authors concluded by saying that for growers trying to assess the impact of plant loss or damage, butternut squash compensated for loss of up to 50% of plant population and up to 33% loss of leaves, particularly if loss/damage occurred early in the season.

The take-home message for the planting pictured here and many others? Compensation may save the day. Let’s hope conditions hold steady or improve and that our plantings’ abilities to compensate are not tested further.

Information regarding the article referenced above:
Title: Moderate Defoliation and Plant Population Losses did not Reduce Yield or Quality of Butternut Squash
Authors: Anusuya (Anu) Rangarajan (Cornell Univ.), Betsy A. Ingall (Cornell Univ.), Michael D. Orzolek (Penn State Univ.), and Lewis Otjen (Penn State Univ.).
Source: HortTechnology July-September 2003, 13(3):463-468 (https://journals.ashs.org/horttech/view/journals/horttech/13/3/article-p463.xml)

More and Better Tools to Help Respond Effectively to Weather-related Challenges

A vegetable farmer pointed out to me recently that “rain” is a four-letter word and that like other ones, he likes rain to fall in just the right amount and at just the right time. Well, although we can’t control when, where, or how much rain will fall, many people in agriculture and the area known as climate services are working to develop reliable forecasts of and effective responses to current and future weather.

Shared commitments to that goal were evident throughout the recent Climate Services Summit (https://climate.osu.edu/news/byrd-center-hosts-ohio-climate-services-summit) coordinated by the State Climate Office of Ohio based at The OSU (https://climate.osu.edu/). Just as important, steps to providing farmers and others with better decision-aids also became clearer through discussions at the program. Ohio State University Extension contributes to the process – for example, see resources, programs, and input offered by Aaron Wilson, Jason Cervenec, and John Fulton – and addressing weather-related challenges and needs of vegetable growers will be important going forward. These were summarized well in two recent reports (https://www.climatehubs.oce.usda.gov/archive/sites/default/files/Midwest_Climate_And_Specialty_Crops_2015_508.pdf and https://store.extension.iastate.edu/product/15448) but more input is always welcome.

Throughout much of this field planting season, many have needed to scramble, improvise, and work round the clock to get work done as weather, soil, labor, and other conditions allowed. It seems that most have experienced the dark side of their share of passing fronts, with few farms experiencing clear skies and calm winds for extended periods. Overall, this seems consistent with information in http://glisa.umich.edu/media/files/GLISA%202%20Pager%202019.pdf (GLISA also participated in the recent Summit). Field and high tunnel plantings have been affected in their own ways by recent conditions, although it is fair to say that most high tunnel plantings were able to remain on schedule, an important early step toward a successful season. Ideally, we will soon see that high tunnels are just one of many key tools available to help maintain and enhance vegetable production amidst changing and increasingly extreme conditions.

Research newly Completed and Started

High tunnel studies are affected by weather. However, typically, high tunnel work continues when some operations in open field production are halted. Like growers, the Vegetable Production Systems Lab (VPSL is transitioning to full “summer mode” as conditions allow. See the six panels below for snapshots of a portion of our recent and near-term activities and don’t hesitate to contact us for more information or if we can assist another way.

Matt Kleinhenz (kleinhenz.1@osu.edu; 330.263.3810)

Five-year soil balancing project results

Another wet spring, and many farmers postpone field work awaiting drier conditions. Could improved drainage be obtained through the application of common gypsum? This is one of the claims made by many consultants and farmers who use a practice called soil balancing.

Ohio State’s five-year study on soil balancing has been mentioned in previous VegNet articles. The project involved multiple long-term field tests, as well as interviews and surveys to better document practices and beliefs surrounding soil balancing. Despite a lack of past research proving soil balancing’s effectiveness, we found that the practice is used heavily by organic and conventional farmers in our region to reduce weeds, and improve soil quality, crop quality, and yields. While we were unable to demonstrate improvements in crop yields or quality, we did see limited effects on soil quality and weed populations in some of our test sites during the final year of the study.

Defining Soil Balancing

Traditionally, soil balancing strives to keep base cations calcium (Ca), magnesium (Mg), and potassium (K) at a recommended ideal ratio (typically 64:10:5). Although long practiced by farmers, soil balancing is not recommended by most researchers and Extension educators. Our study indicated around half of organic corn growers in the Midwest used a soil balancing approach, but more than 75% of the Extension researchers we surveyed felt soil balancing had no scientific merit.

It’s true that most soil balancing studies done in the past 20 years have reported the practice had no effect on production. However, our research reveals several potential gaps in these studies. Consultants and farmers we interviewed commonly reported that soil balancing improved overall soil quality and structure, which led to improved drainage and reduced weeds. While farmers also reported improved yields and profit, it was generally not the first improvement they mentioned. Interviewees noted that these improvement often happened gradually over several years. In short, past research may not have captured long range positive effects. Most recent studies were short-term, lasting one or two years; were conducted in a greenhouse rather than field; focused only on improved yields; and were conducted on limited types of soils. (Chaganti and Culman, 2017)

We also found that many farmers pair cation balancing with other soil improvement practices such as cover crops and biostimulants. The goal, according to the “balancers” we spoke with, is to improve the physical and biological properties of the soil.

Field Testing

Using both on-farm and Ohio State research station sites, we collected data on soils, weeds, and crops, while applying a variety of soil amendments to change Ca:Mg ratios. We measured crop quality using Brix, color, size, and other characteristics specific to individual crops. Vegetable crops included tomato, butternut squash, cabbage, popcorn, and edamame. Agronomic field crop trials were conducted as well.

We were unable to document any treatment effect on yield or crop quality. In the last year of testing, we did see effects on weed populations (either lower weed populations overall or lower populations of foxtail on “balanced” soils) and on soil root resistance (indicating improved soil structure with higher Ca saturation). These effects appeared only on some fields, but they do support our hypothesis that the positive results of soil balancing are related to improvements in soil structure and drainage. We hope to continue monitoring these fields to see if results become more consistent over time.

Recommendations

For now, we are unable to officially encourage or discourage the use of soil balancing. The following recommendations are based on field trials and on the experience and advice of our stakeholder advisory committee.

  • Soil test data is critical to making informed decisions about what to apply. Some Ohio soils may already have large concentrations of Ca due to Ohio’s limestone bedrock.
  • Watch your pH if using lime. Gypsum is a better choice to change the Ca level without affecting pH and it also provides sulfur.
  • Soils with a CEC below 10 may develop deficiencies. In soils with a low holding capacity for cations, excess Ca can lead quickly to deficiency levels of K, and possibly Mg. We did work in fields with Ca saturations well above 80% and observed K deficiencies in the soil and vegetables in these situations.
  • Consider economic factors. The higher your CEC, the more time and amendments will be needed to increase the Ca:Mg ratio. At some point—depending on the amount of change needed and the value of your crop—using soil balancing becomes an expensive practice.
  • Any time you try a new practice, monitor the results. If possible, try using the new practice on only part of your farm and compare it with a similarly managed area to see if the new technique is making a positive contribution over time.

With widespread use of the practice, soil balancing is a pertinent area for research and cooperative education. Our team hopes to continue studying the practices and long-term effects of soil balancing on a larger variety of soils. Drawing on experiment data and the experience of farmers and consultants, we will work toward guidelines and toward a mutual understanding of soil balancing.

Read more about this study at the Soil Balancing Project Site or the Vegetable Production Systems Laboratory. This work is supported by Organic Agriculture Research & Extension funding grant no. 2014-51300-22331/project accession no. 1003905 from the USDA National Institute of Food and Agriculture.

 

Growers and Researchers continue to Study Grafted Vegetable Plants

In Ohio, full-time study of grafted vegetable plants as products (i.e., sources of income) and production tools began more than ten years ago. Much has been learned and the popularity of grafted plants continues to trend upward. However, growers and researchers continue to ask many large, detailed, and tough questions about the roles of grafted plants in commercial production going forward. “Do grafted plants pay?” may be the most often asked and significant question. This brief article cannot address that question definitively for all readers due to the specific circumstances of each farm, field, crop, planting, season, etc. However, peoples’ collective understanding of the pros and cons of using grafted plants and of conditions leading to a good return on investment after using them is improving. As it does, success with grafted plants improves and their use increases. Regardless, additional research is needed. The three panels below briefly summarize a portion of the vegetable grafting research underway in Ohio in 2019. Please contact us if you would like to learn more about this work and stay tuned to VegNet and other outlets for updates.

Matt Kleinhenz, ph. 330.263.3810, email kleinhenz.1@osu.edu

Grower, Gardener, Educator, and Researcher – All can Gain from Vegetable Grafting

Grafting is an ancient technology currently coming of age, helping vegetable growers and gardeners and educators and researchers in Ohio and the U.S. address some of today’s most significant challenges. Find out more at two upcoming programs.

The Muck Crops School on January 10 in Willard, OH will include a presentation by grafting expert Dr. Richard Hassell of Clemson University. He will outline progress made in developing rootstock (RS) varieties resistant to Phytopthora capsici, a devastating disease of pepper, tomato, melon, and other major vegetable crops. In grafting, root systems of RS varieties are spliced to the shoots of scion varieties, creating physical hybrids that often out-perform ungrafted versions of the scion variety, especially under stressful conditions. Indeed, creating physical hybrids opens key opportunities in production, research, and education. Contact OSUE-Huron County (https://huron.osu.edu/home) about attending the Muck Crops School on Jan 10, 2019.

The Ohio Produce Network program on January 16-17 in Dublin, OH will include two sessions on grafting, both occurring on January 16. Session 1 will feature presentations and discussion led by six additional experts: Dr. Chris Gunter (NCSU), Dr. Matt Kleinhenz (The OSU), Dr. Sally Miller (The OSU), Cameron Way (Way Farms), Chuck Mohler (Sweet Corn Charlie Farms), and Ed Kerlikowske (http://lifegivingfruit.com/). A representative of TriHishtil (http://www.trihishtil.com/), a major supplier of grafted plants, may also participate. Together, the six presenters and discussion leaders will provide a comprehensive, up-to-date, and stakeholder-focused summary of grafted plants as sources of income and production tools. Session 2, later on Jan 16, will deliver individualized training in making grafted plants, a straightforward process that can be completed in many settings. See http://www.opgma.org/ohio-produce-network/ about attending the OPN on Jan 16-17, 2019.

Contact Matt Kleinhenz (330.263.3810, kleinhenz.1@osu.edu) for additional information about these programs and see http://www.vegetablegrafting.org/ and http://u.osu.edu/vegprolab/research-areas/grafting-2/ for more information about vegetable grafting.