Could a Soil Fumigant be Used as a Bio-Stimulant?

Common knowledge or conventional wisdom is just that, something that is generally accepted as fact, until it isn’t. We can look throughout history and find plenty of things that were generally accepted until new discoveries challenged and disproved those things. For decades, the living, microscopic portion of our soils has been somewhat of a mystery. If the organism wouldn’t grow in a petri dish, it was difficult to know if it was present and if its’ populations were increasing or decreasing. Modern techniques have provided far greater insight into the microbial world that lives unseen in our soils. We can now extract genetic information from a teaspoon of soil and determine which organisms are present through their genetic fingerprints.

Now on to soil fumigation: the process of applying a liquid below the soil surface which subsequently transitions to the gas phase and the vapors move through the soil profile. These vapors are present from days to weeks based on the chemistry and application technique. Depending on the fumigant used, the vapors can be toxic to soil borne pathogens, nematodes, and weed seeds. This is why soil fumigants were originally put into use, to control soil borne diseases. Based on this information, it is easy to jump to the conclusion that soil fumigation would have devastating impacts on soil microbial communities. In fact, we often hear that soil fumigants sterilize the soil. Reducing populations of certain organisms such as Fusarium or Rhizoctonia are advantageous, but there are multitudes of organisms that are beneficial to plant growth and soil function, and it has been assumed that these have been equally reduced like the pathogens.

Enter modern techniques. A group of scientists at the University of Florida have been investigating the impact of soil fumigation on microbial communities and recently published some of their findings ( This group looked at soil microbial communities in a plasticulture tomato production system before and after fumigation with several different fumigant treatments as well as beds that were left untreated. First off, even the most effective soil fumigants don’t sterilize soils. There are a multitude of organisms that were found shortly after fumigation. They also found that fumigant treatments with greater than 60% chloropicrin consistently increased tomato yield, which is why producers use these products. The use of fumigants resulted in significant changes in the soil microbial communities and fumigants reduced the microbial diversity of soils, but these changes are temporary and those soils reverted to their original state by the next growing season. Some of these changes in microbial complexity could hinder some of the major functions of microbes in the soil such as nitrogen metabolism and carbon fixation. So, these findings do not come as a huge surprise to anyone who is familiar with soil fumigants and how they function.

Castellano-Hinojosa et al. 2024 – Graphical Abstract

But you know how we mentioned common knowledge earlier, well here’s the challenge to that. Most readers of this article are probably familiar with beneficial organisms that are naturally present in the soil or can be purchased and applied, often referred to as “bug in a jug” products. Some of the most common products available contain various species of Bacillus bacteria or Trichoderma fungi. These researchers found that the abundance of Trichoderma was increased after treating the soil with chloropicrin, even more than the untreated. Yes, you read that correctly. The abundance of Trichoderma was greater after treatment with chloropicrin compared to doing nothing and that change persisted until the end of harvest. A similar pattern was observed for Bacillus and Paenibacillus species, both of which serve beneficial roles in the soil.

Soil fumigants play a critical role in many production systems and are a necessity to manage major yield limiting pests. However, are these the only uses for soil fumigants? Based on this University of Florida research, could we use chloropicrin, a soil fumigant, to increase the abundance of naturally occurring beneficials like Trichoderma? Could a soil fumigant be used in the role of a bio-stimulant? That would certainly be a challenge to conventional wisdom.

Feel free to contact us to discuss these ideas further and to learn more about what chloropicrin could do in your field.

  1. Ref: Castellano-Hinojosa A, Karlsen-Ayala E, Boyd NS, Strauss SL (2024) Impact of repeated fumigant applications on soil properties, crop yield, and microbial communities in a plastic-mulched tomato production system. Science of the Total Environment 919: 170659; doi: ↩︎

TriEst Ag Group: Partners in Profitability

There is a lot of talk about sustainability and regeneration in agriculture these days. But what do those terms really mean? If you ask five people, you might get five different definitions. But for Josh Mays, Director of Agronomy for TriEst Ag Group, it all starts with profitability. Mays says “We should all be critical of how farming practices impact the ecosystems around the farm, but we can’t be sustainable without being profitable. There is nothing sustainable about the loss of farms in the United States due to financial instability.”

To put that statement into perspective there are only an estimated 1.89 million farms to feed 332 million people in the United States or 0.5%. According to Yahoo Finance, America has had an average loss of nearly 1.8 million acres of farmland per year since 2015.

He says profitability always has been important, but it is even more so today when there are so many factors that could take valuable farmland out of production. Challenges include competition from urban development, trouble sourcing labor, regulatory burdens, foreign competition impacting markets and the aging demographic of specialty crop growers.

“How do we keep our growers profitable? The economics need to be better for them to farm their land than to sell it for development or other uses,” Mays says. “Our intention at TriEst Ag Group is to help farmers keep farming.”

The company’s core customer base is in plasticulture specialty crops like strawberries, tomatoes and peppers. Other key customers include bare ground sweet potatoes, potatoes, snap beans, sweet corn, and vegetable crops.

Green Bean Field Trial in Florida


Mays says TriEst Ag Group helps growers key in on profitability by learning about their operations and finding ways that their products and services can be a benefit.

“We go very deep working with growers. That is what my job is all about,” he adds. “We take a step beyond just our products to discover what is the best approach to profitability for each farm. We work with growers to go over fertility programs, to consider variety selection, field selection and testing for what levels of pest problems they have in their soils. We holistically build a program that includes our products where they can help the grower but also are a part of a larger program.

“We are a spoke in the wheel. We want to better understand everything farmers have going on, so we can help them figure out the most economical solution to the challenges they face.”


TriEst Ag Group has a wide range of products and services that can help growers achieve profitability. The company specializes in soil fumigation, irrigation, crop nutrition, equipment, grafted plants, polytunnels, substrate and associated growing systems.

Soil fumigation with two key products, chloropicrin and 1,3-D (TELONE™), has been foundational in helping growers get their specialty crops off to strong, clean starts. Mays says these products have been studied extensively to maximize crop yield, quality and performance, especially since methyl bromide was phased out.

“These two products have been the subject of years of research and millions of dollars invested by universities and the private sector,” he says. “They are now the foundation of what we do to make up for the loss of methyl bromide. 1,3-D is effective in managing nematodes while chloropicrin manages soil-borne pathogens.

“We’ve seen advancements in plasticulture and tarps to create a better barrier that holds these products in the ground longer at higher concentrations. This allows us to consider rate reductions and achieve more efficacy. And it forced us to be more integrated and innovative in our approach to better manage pests. We’ve been successful in doing that through our collaboration with our grower customers.”


Mays says another area of intensive research has been maximizing soil health in fields. The study of the soil microbiome is a hot field now in all of agriculture.

“We are doing a lot of research on how our products interact with the soil microbial system,” Mays says. “We know we must manage nematodes and soil pathogens to produce a healthy crop. We are seeking the best ways to utilize our fumigants to provide the best suppression and have been studying how our fumigants alter the microbiome.”

The research has turned up encouraging results. The use of chloropicrin and 1,3-D has been shown to not ‘sterilize the soil’ as some have said.

“Science shows when you apply these products, you shift the microbial community. You get shifts of certain organisms, and there are others that take their place that are often beneficial organisms. We are learning now how to better utilize that shift. There is an entire new science emerging around the interaction of those microbes and our products, across a wide range of rates and new crops.”


The goal of TriEst Ag Group’s relationships with growers is to help them get more productivity and profitability from each acre of their crops.

“If we can learn new ways to innovate and create more yield on an acre and seek ways to be more efficient and reduce costs where we can, that is key to profitability,” Mays says. “If we were to take our core soil fumigants out of the equation, then you might see specialty crop yields drop by 30%. That will take 30% more acres of land to replace, and all the other inputs needed to grow the crop. That is not sustainable or profitable. We take great pride in working closely with our growers to bring them solutions that keeps that acre of farmland in farming.”


If you are interested in learning more about TriEst Ag Group’s products and services contact us today.

Low Dose Chloropicrin – When SweetPotato Set is at Stake

We hinted at the end of our blog article – 2023 Trial: Impacts of Soil Fumigation of Tobaccothat we also did trials on sweetpotatoes that compared mixtures on Enterolobii nematode control and dual applications on seed production. Track number 1: why high why nematodes? Answered further in this article. Track number 2: why did we get late season resurgence?

In this blog we will go into more detail on those trials, the outcomes, and the implications.

In the Summer/Fall of 2022 TriEst Ag Group did a mixture study that focused on Enterolobii in Nash County, NC. The trial evaluated the use of TELONETM, C15, and C35 at 6 GPA (22 GPA broadcast) shank applied in-row 14” deep with 10” of stack. The row was re-shaped to 5-8” in front of planter. The field had a heavy Enterolobii (Guava Root Knot Nematode or GRKN) pressure.

We fumigated the field May 11, 2022, the field was planted June 14, 2022, and harvested October 24th, 2022.

This chart shows that Guava Root Knot Nematode (GRKN) resurged in all 3 plots. Damage was observed in all plots as well, but was worst in C35, which would be expected from the treatment with the least amount of TELONE being applied.

Despite C35 having the worst GRKN levels and damage it still provided the highest yields and the best crop throw showing a clear benefit to having Chloropicrin in the system. For this growing region that is focused on table stock production, bushes of #1’s per acre is critical.

The results of this trial left us with a significant observation and question, why did we have the highest yield in a treatment with the highest volume of nematodes at seasons end?

Nematode pressures rose in the last 30 days of the crop, even with very good suppression of the pest after each treatment application. Why did we see a late season resurgence of nematodes? How mobile is GRKN and are they moving from untreated areas back into the root zone? Would a deeper application work? Would a wider area of application make a difference?

While we answer the question of why did we have the highest yield in a treatment with the highest volume of nematodes at season’s end in this article the remaining questions this trial spurred we will answer in a future article on another field trial from 2023.

Back to the impact of chloropicrin…

The following summer/fall of 2023 we decided to look at TELONE and TELONE with PIC applied in a dual level application to see if we could build off of what we learned in the 2022 trial.

The trail took place in Nash County, NC again, but this trial purposefully had low root knot nematode pressure. The primary goal was to see the impact of Chloropicrin on the crop and build off of what we learned in 2022.

The sweet potato crop in this trial was grown for seed, where growers are targeting heavier tuber sets and smaller size profiles overall, which is what we saw in the 2022 trial harvest.

We fumigated 6/3/2023 with TELONE at 6 GPA in-row (22 gallons broadcast) and TELONE at 6 GPA in-row plus 20lbs PIC100 (75lbs broadcast) in a dual application 8” PIC and 14” TELONE. Everything was shank applied in-row with a ripper bedder at 14” with 10” of stack. The row as reshaped to 5-8” in front of the planter.

The field was planted on 6/23/2023 and the crop was harvested on 10/20/2023.

The conclusion from this trial was that the addition of a low dose of Chloropicrin (75lbs Broadcast/20lbs BER) increased the tuber set. This resulted in a higher yield and smaller size profile overall. This is a big advantage for seed growers. We feel that getting the Chloropicrin dose as close to the where the root system will be (6-8” beneath final planting depth) is important. For nematode management, TELONE should be applied 12-16” deep to treat the highest volume of soil possible, which is why we looked at dual application as opposed to a blend with both products being applied down deep.

In conclusion, the key takeaways from these trials would be that higher sweet potato yields can be achieved when a low dose of Chloropicrin is used to increase set. TELONE is critical for nematode management and depth of application is important in regards to location of the pest in the soil profile. Dual level application with Chloropicrin applied in the root zone and TELONE applied beneath the root zone increases tuber set while also maximizing nematode management.

Remember to subscribe so that you don’t miss our future blog article on our work in sweetpotatoes that will answer the questions of why did we see a late season resurgence of nematodes? How mobile is GRKN and are they moving from untreated areas back into the root zone? Would a deeper application work? Would a wider area of application make a difference?

To learn more now or talk to a representative about seeing what Chloropicrin can do in your field Contact Us Here.

2023 Trial: Impacts of Soil Fumigation of Tobacco

In our last post we covered the Impacts of Fall & Spring Fumigation of Tobacco.

Based on the findings from those trials in 2021 and 2022 TriEst wanted to take a deeper look at finding unique application and timing solutions to better meet a grower’s nematode and disease pressures. The 2023 trial focused on sampling depths to map location of pests, dual depth applications to place the correct product in the right place, and a variation of treatments to proof out these concepts.

We prepared different application levels to best place TELONE™ and Chloropicrin where nematode problems were the previous season at depths of 12” to 18” due to cool soil temperatures in early spring driving nematodes down to more temperate soil levels. In the Fall, nematodes are up high in the soil profile due to warmer soil temperatures and available food sources from crop roots being grown through the summer. Fall is a challenging application time for tobacco growers due to harvest of tobacco along with rotational crops and timing of crop contracts for the next season. In most cases, growers haven’t finalized plans for planted tobacco acres for the following season until late Winter. This makes finding a Spring application solution critically important.

Soil samples were pulled monthly throughout the season at dual depths of 0” – 8” and 9” – 16” from both in the row and the row middles. This sampling protocol allowed us to map the movement of nematodes from deeper in the soil profile up into the root system, as well as from the row middles into the row. Shown below in the soil samples. The darker color soil (right) is from the deeper level of 9” – 16”. Note the soil type differences in the soil probe and final sample collection bags, this visually highlights the potential need for dual application, as nematodes in the Spring are concentrated in the deeper soil profile (9-16”) and soil borne pathogens in the shallower soil profile (0-8”).

We designed an application strategy that would place TELONE™ and Chloropicrin within the soil sample zones described above and compared the dual depth application to the grower standard single depth application on the bottom of the shank. All applications were made in-row treating 25% of an acre, with a 12” application zone on 48” row centers. See the picture below, the top outlet is 8” below the soil line and the bottom outlet is 14” below the soil line. At the time of application, there will be an additional 8-10” of soil stacked on top during the bedding process.

Unlike our trial in 2022, this trial didn’t show a late season nematode resurgence. Pre-fumigation root knot nematode levels warranted treatment, but all treatments cleaned up this issue. We expected additional nematode pressure to come from the row middles and to move up from below our application depths, which happened in 2022. Yields were not impacted by nematode pressure; however, they were heavily impacted by Grenville Wilt. The significant differences you see in yield in the chart below between the non-treated check and all other fumigant treatments are due to early season growth responses from Chloropicrin and suppression of Granville Wilt. All fumigant treatments performed well over the non-treated check, with little separation between the grower standard of PIC100 at 50 lbs/acre and the additional treatments including TELONE™. Again, this was a result of lower than anticipated root knot nematode levels from mid-season through harvest. The highest yielding treatment was the dual depth application of TELONE™ and Chloropicrin, likely due to getting Chloropicrin closer to the root system of the plant with a shallower application point than the grower standard treatment.

Guava Root Nematode pressures are rising in sweetpotatoes so we did a similar trial that compared in-row vs broadcast applications at different depths with high/low sampling. Unlike the tobacco trial of 2023 the pests showed up to dinner.

Be sure to subscribe to our blog so you don’t miss the details on the sweetpotato trial and other trials.

If you’d like more in-depth information on our trials and what TriEst can do for your farm be sure to reach out to us. Contact Us Here

You can also view a video from the 2023 Tobacco Field Trial on our YouTube Channel Here.

Impacts of Fall & Spring Fumigation of Tobacco

This project was established in East Central NC originally in 2021 to evaluate the effects of TELONE ™ II and Chloropicrin (PIC) on nematode suppression, Granville wilt suppression, and tobacco yield and quality.

Yield losses from crop “melting” late season have become common in the greater tobacco production regions. This is a complex issue of harvest timing, weather conditions, disease, and nematode pressure. Growers are consolidating and getting larger with same infrastructure, which is putting more pressure on fumigants to protect the crop longer. Companies also want more overripe tobacco, putting more pressure on late season harvests.

In tobacco, maturity windows are critical to management, when everything matures at once and growers struggle to get around the crop and harvest in a timely manner. In 2021, our first tobacco blend study resulted in the grower standard of 200# PIC (#50 BER) being the better treatment overall with more early vigor than treatment blends containing TELONE. The plots with PIC100 showed a 5 to 7 day earlier maturity rate over PIC/TELONE blends, leading us to the question of – is it possible to stagger harvest between the products?

If PIC is maintaining earlier maturity, that needed to be accounted for in harvest planning. We consolidated our 2021 findings into our set of treatments for the 2022 tobacco study with another central North Carolina tobacco grower. Similar to 2021, treatments containing only Chloropicrin (PIC) in the Spring showed the best early vigor, highest lower stalk yields, and overall best plant structure.

Once harvest began, we found that late season nematode pressures resulted in higher wilt levels and caused yield losses. There was not much separation between the Spring PIC100 and PIC60 plots in nematode control (Spring application, cool soil temps, and depth of pest may have played a role). Spring PIC application plots looked best prior to nematode pressure and had the best first and second harvest yields. In instances where Root Knot Nematode isn’t present PIC100 is the most economical solution.

All of the plots where TELONE was Fall applied had a significant impact on season long nematode suppression and resulted in the highest yielding plots overall. While Fall applied TELONE treated the late season nematode problem and protected yields, it didn’t necessarily cause the yield gains. The Spring PIC60 application didn’t solve the late season nematode problem. Knowing nematode levels and location in the field pre-soil fumigation is critical.

Based on these findings TriEst’s intention is to take a deeper look at finding unique application and timing solutions that meet a grower’s needs. We have more trials in the ground now improving on soil fumigation application timing and depths. Our next blog will be on our 2023 trials that focus on sampling depths, the probes, and treatments. In the 3rd blog of this series, we will go over those 2023 trial results.

So stayed tuned and be sure to subscribe so you don’t miss the latest information.

The Badger Common’Tater: An Interview with Josh Mays of TriEst Ag Group

Today, we’re absolutely thrilled to share some news with you. The July issue of the Wisconsin Potato and Vegetable Growers Association’s The Badger Common’Tater features a wonderful, in-depth interview with our own Corporate Agronomist, Josh Mays! This entertaining conversation delves into Josh’s background, why he joined the company, the innovative techniques that TriEst uses, and a detailed conversation about chloropicrin-based products in crop protection.

Don’t Miss the July Crop Protection Issue by the WPVGA The Badger Common’Tater.

If you’re curious to learn more about Josh Mays and the dedicated work happening at TriEst Ag Group, be sure to grab a copy of The Badger Common‘Tater’s July Crop Protection issue. You can find the article on their website here: JULY 2023 ISSUE of the Badger Common’Tater

This interview is a must-read for farmers, industry professionals, and anyone passionate about the future of agriculture.

Soil to Substrate: Key Irrigation and Fertigation Ideas for Long Cane Raspberries

The Comparison

Traditional soil production for soft fruit crops is a buffered system that is slow to change, whether good or bad. Fertigation mistakes in a traditional soil system isn’t necessarily going to be detrimental, or result is major pH or nutrient changes. For the same reasons, soil deficiencies or incorrect pH ranges are more difficult to correct in traditional systems.

The difference in a substrate system is significant. It is a low volume potted container area that is essentially fed by an IV nutrient solution, so fertigation changes can result in major nutrient or pH shifts within a matter of hours. So, this situation is both good and bad – you can correct your mistakes very quickly and you can make mistakes very quickly. Think of substrate as a high risk, high reward type system where your attention to detail is very important.

Moving forward with those differences in growing systems pointed out let’s lay out some key ideas for growing.

Plant Nutrition and PH

Starting with the right pH is key in a soil system for berries, or you’ll be fighting it all season long, but impact in season is minimal with the right fertility program. Most soil systems are high volume of fertilizers and water, with low frequency of runs for irrigation and fertigation. Fertility in soil systems are referred to in terms of pounds per acre. The southeast typically has programs of 150-30-200#/acre NPK with 30-50# S and 40-50# Ca. Fertigation is supplied commonly with potassium nitrate/calcium nitrate/UAN style blends (a 5-1-7 with 2% Ca for example). We do a lot of these type blends in traditional soil production of soft fruit, with sulfur being supplied as a supplement.

In a substrate system, the program is the opposite of a soils system. Low volume and high frequency systems run typically for 2-3 minutes at a time 20-30 times daily. Fertigation is driven by PPM (parts per million) to target crops by each stage every irrigation cycle. Fertility isn’t driven by pounds of nutrient applied per acre, but crop demand of a balanced nutrient solution based on irrigation needs. It is also critical to realize that rapid pH manipulation is possible through water treatment and fertilizer selection. Just think about the size of the pot and the tight area the plant is in. So, as a grower, you have to re-calibrate yourself in this type of system to be more targeted and understand how quickly changes can be made.

Water Quality

Water quality is the first factor in determining a proper nutrient and irrigation plan for a substrate crop. Well, municipal, and surface water is variable and should be regularly tested for pH, EC, and iron. Managing pH is very important particularly in substrate systems as highlighted earlier. Making assumptions about your source water can lead to big mistakes, test first.

Injection Systems and Fertilizer Sources

When you look at injection systems to create a fertility base like we’ve been discussing it is generally a two-stage injection system that will allow growers to run one tank that is calcium based and another being sulfur based. Calcium and sulfur don’t play nice as fertilizer concentrates, so this split is the most natural way to begin your fertility program. Both tanks can be run as a diluted mix simultaneously, pending quality and dilution rate.

Nutrient form matters! The form you choose to use can have a large impact on your pH (especially nitrogen). Water-soluble blends are the recommended best option for a substrate system due to the ability for customization. Drip grade liquid fertilizers are an option with reduced labor, but it can’t be customized as much, as the scale for drip fertigation is much larger and is made in greater quantities typically. There are many options to find the same end goal for nutrition, as long as the product form/ratios are correct.

Last Thoughts

There are a lot of factors that need to be monitored in both substrate and soil systems. You can go from a very simple, labor intensive style to monitor pH, water quality, nutrients, and E/C which does work or you can start adding layers of sensors and automation. To learn more you can reach out to our team and they can help you research solutions that will work best for you and your substrate production needs.

Green Beans: Low Rate Fumigation Trial

Green Beans

Building off of our traditional success in tobacco and our more recent watermelon results in 2020-2021, we wanted to trial our low rate system in another crop that fit the specifications outlined earlier; 60-120 day crop, high value, not currently being fumigated as a standard practice. An opportunity was found in Florida with fresh market green beans. After reviewing the economics of green bean production in this region and considering the chloropicrin rate ranges we had seen increased vigor/yields in other crops, the following protocol was set for the trial:

  • Evaluate 85# broadcast (25# BER) and 130# broadcast (40# BER) on fresh market green bean
  • Fumigation was applied bare-ground with a single application shank at a 6” depth while stacking a 12” bed at application. The grower followed this by double bedding immediately following the fumigation pass to increase stack from 12” to 15-18”, resulting in a final application depth of 21-24”. At planting, the bed is knocked down to an 8-10” pressed bed that’s prepared for direct seeding. This results in seed being planted directly into the fumigated zone.

The results of this study were very successful. The crop vigor and uniformity were significantly better in fumigated treatments and had a direct correlation to rate. Both rates resulted in better seed germination, larger root systems, uniform plant populations and enhanced growth versus non-fumigated. Yield results were the following:

The results of this study are quite drastic, but this work was done in a heavily cropped system in tight rotations.  This project was in the third rotation of green bean on this farm, with no previous fumigation on that specific crop and grower standard yields were below average. With that said, we’ve drawn the following conclusions and thoughts:

  • Chloropicrin has the potential to maintain higher than average yields in multiple cropping cycles of green bean
  • Consistent emergence and uniform growth resulted in more yield bearing plants per acre and harvest efficiency
  • Future projects will focus on fresh rotations in both Fall and Spring, to determine ideal timing of applications and efficient use of Chloropicrin

We hope you continue with us on our low rate trial journey. Sign-up for our blogs today to keep up.

To learn more about what soil fumigation can do in your fields contact a sales rep in your area by clicking here.

Potato School Coming December 13

Register Now for: POTATO SCHOOL
Tuesday, December 13, Register online:
Potato School – Eventbrite

It is FREE and will be a VIRTUAL ONLINE EVENT.
Come join us for a robust day of learning and discussion. We have an excellent line-up of speakers planned.

Who you will hear and what you will learn:

  • Dr. Steve Culman

    Washington State University’s Soil Health Endowed Chair:

  • Dr. Gary Secor

    North Dakota State University Professor Plant Pathology Department:

  • Dr. Chad Hutchinson

    TriCal Group Global Director Potato Research and Market Support:

  • Grower Panel
  • Dr. Randy Huckaba

    Teleos Ag Solutions Director of Product R&D:

  • Jonathan Vink

    Sales And Service at Douglas Agricultural Services Inc.:

*Additional Speakers To Be Added!
CEU Credits have been be applied for and will be offered.

Part II: A Deeper Look into Grafted Watermelon Production and Management

Harvested Watermelons

In our last blog post we took a deeper look into grafted watermelon production and management by reviewing a 2020 watermelon trial in central North Carolina. In this post we want take you through year 2 results and our findings. The key focus points of the trial were increasing yields and maturity window of grafted plants using chloropicrin.

Trial details for background

  • The trial was on watermelons grown on plasticulture using TIF film since we found the best results the year prior with using that.
  • We made shank applied fumigant application using a Reddick Equipment Company RMC plastic layer 25 days prior to planting.
  • The grower had watermelons on this particular piece of land on a 3 year rotation with sweet corn, small grain, and tomatoes.
  • The land had heavy root knot nematode pressure and low fusarium wilt pressure so the Carolina Strong Back rootstock was used for the grafted watermelon plants.
  • The trial was planted on 8’ row centers x 3’ standard plant spacing (1,815 plants/acre) and 8’ row centers x 4’ grafted plant spacing (1,316 plants/acre).
  • We used 25% pollinators in-row between every 3rd and 4th seedless plant.

Harvest Events

  • The trial fields allowed for 3 harvest events.
    • June 30 (74 DAP)
    • July 12 (88 DAP)
    • July 26 (102 DAP)
  • The Joyride melon used is an 86 day melon.
  • The grafted maturity is the same as the standard Joyride plant maturity, but heavier yields were shifted 5-7 days.
  • We saw a strong yield response to the fumigant applications and vine health remained great all the way through final harvest on July 26th.

In summary, we saw results similar to our findings in 2020.

  • Chloropicrin is increasing yields in both non-grafted and grafted plant production systems
  • Fertility changes and addition of chloropicrin are speeding up grafted plant maturity
  • First harvest of grafted is approximately half of non-grafted, but the second harvest of grafted is much heavier
  • Longer harvest windows are possible with grafted plants, due to increased plant growth and durability to harvests
  • No significant differences were seen in size profiles or sugar content/brix between treatments

We saw comparable results in 4 different trials of similar design across North Carolina, Georgia and Florida in 2022. Some key findings:

Standard plant yields are increasing use of chloropicrin

  • North Carolina – 34% increase
    • Florida – 16% and 15% increase
    • Georgia – 20% increase

Grafted plant yields are increasing with the use of chloropicrin and specific fertility protocols

  • North Carolina – 22% increase
    • Florida – 12% and 23% increase
    • Georgia – 14% increase

Combining grafted plants and fumigation with chloropicrin is providing dramatic yield increases over grower standard practice yields in all trial areas

  • North Carolina – 70% increase
    • Florida – 28% and 44% increase
    • Georgia – 28% increase

To learn more please contact our very knowledgeable team at TriEst and be sure to sign up for the next installation of the TriEst Ag News series.