Jesse: This afternoon we are speaking with Dr. Norman Arancon from the University of Hawaii in Hilo. As we at Hiwassee Products were researching the science of vermicomposting, the name Norman Arancon PhD kept coming up in the literature and the studies that were referenced. I’ve been looking forward for a long time to speaking with you and finding out more about your trials, and the things you've studied. Also joining me today is Natalie from Heart and Soil magazine. This interview will be part of the regenerative resource that we're working on together.

Norman: Well, Aloha and good morning everybody. My name is Norman Arancon. I currently serve as a professor of horticulture and director of the College of Agriculture Forestry and Natural Resource Management here the University of Hawaii at Hilo.

Natalie: It is awesome to have you with us, Dr. Norman. You've always been on my radar who I've wanted to be in the room with, so including you in this Regenerative Resource is a deep honor. I'm Natalie Forstbauer, founder and editor-in-chief of Heart and Soil Magazine. we are your source for global regeneration, grounded in soil, driven by health and inspired by transformation.

Jesse: Norman, could you start by giving us a bit of your background in academia and what got you interested in vermicomposting and worms, and why that became your main field of study?

Norman: I started with a bachelor's degree in agriculture, a major in crop and soil science, a combination of fields. This was in the Philippines way back then in the 80s. then after that degree, I started teaching at the same school, that’s Xavier University in Cagayan De Oro City in the Philippines. I taught there for a number of years before I got a scholarship in Australia studying further sustainable agriculture in the 90s, so I did a postgraduate degree in agricultural sciences in the University of Queensland in Australia.

I went back and headed up a center for sustainable agriculture at Xavier University, headed the research and documentation department of sustainable agriculture and later became director of that center. Our mission was to promote sustainable agriculture in the Philippines. It was a new idea then, and it was exciting to see the conversion of farmers from conventional to sustainable farmers in the field.

In the late 90s, I was awarded a Fulbright scholarship to study sustainability in agriculture then. I chose Ohio State University as my institution to study. I chose it because one of my professors in Xavier University graduated from Ohio State, and I thought there's no better school than to be in a school where my previous professor studied for his PhD in crop sciences. I went there and did my PhD and master's degree in environmental science, but it was an interdisciplinary program where I was able to focus on agriculture and vermicomposting. It was Dr. Clive Edwards, who was a the pioneer in soil ecology and vermicomposting, who convinced me to study earthworms and vermicomposting with him.

We did pioneering work in the research of vermicompost, starting in the greenhouse with a former student of his, Rola Atia. Then I continued that onto the field to confirm that what we found in the greenhouse was consistent with what happens in the field – and it was. From then on I got hooked on the study of worms and vermicompost and its effects on plants, not just annuals and flowering plants, but also food crops. It enhanced my passion for sustainability in agriculture because earthworms are very much part of soil biology and the augmentation what a healthy soil should be for plants.

Jesse: Could you describe of some of the studies you conducted? Were those at Ohio State or mostly at Hilo?

Norman: Mostly at Ohio State, because that formal part of my master's thesis became my dissertation for my PhD then. I worked on several research projects on the utilization of vermicompost in the field, starting with a couple of plants that we studied as a role plan just to make sure that it carries over or it's representative of most plants, petunias, marigolds and other flowering plants. Then we went on to study the effects on tomatoes, peppers, strawberries, grapes.

When I came here to the University of Hawaii Hilo, I did research in vermicompost using ginger also kalo and uala and sweet potatoes. Then in the classroom I did several studies of vermicompost and incorporated it into hydroponics. We didn’t just use the solid form of vermicompost, we also extracted the aqueous form and incorporated it in hydroponics ,which is popular here because we lack soil. With the hydroponics, you can grow plants with just water and nutrition. The problem is that when you add nutrition to the hydroponics, it's all 100% chemical fertilizers. We proved that you can replace 50% of the chemical nutrition with vermicompost tea, and grow plants that are just as good.

Jesse: What else are you feeding them? Is it pretty much what they would have gotten from the soil?

Norman: Yes, when you do hydroponics, it's all by recipe. You have chemical fertilizers and you put them in water, then you just take half of that and put 3% vermicompost into the mix. The results were astronomical. Nobody expected it. We know now that what we add to the soil is not just nutrition, it's all the other stuff in the vermicompost. During the vermicomposting process, the microbial biomass, the microorganisms that are present in vermicompost produce more than nutrition. They produce plant growth hormones. The hormones that we looked at are gibberellic acid, cytokinins, and auxins. They're all present in vermicompost in different quantities, depending on what source of material you produce your vermicompost from.

We tried all kinds of vermicomposts from animal manure to food wastes. At Ohio State, we collaborated with vermicomposters in Oregon called the Oregon Soil Corporation. They supplied us with vermicompost made from food waste. We were awarded a grant from USDA to study that further, and we saw that with adding food waste vermicompost into crops, it sped up the process of flowering for petunias and also increased the fruiting and flowering of tomatoes, peppers, and even grapes. The sable grapes that we looked at in North Kingsville, Ohio, had significantly increased yields by using vermicompost, even if they were already 10 years old.

One of the case studies we've seen here in Hawaii was the application of vermicompost into a field that had some root rot disease for ginger. One of our farmers here produces organic ginger shipped to the mainland. One of our plant pathologists here at Hilo found that his soil had a root rot disease called Pythium Selenicereum.. The problem was that the farmer already planted ginger. The plant pathologist said if you have that in your soil you just have to abandon the soil. He said, if I have to abandon it, I might as well just apply something to see if I can save my ginger. he applied vermicompost into his plots and left it. After six or seven months, he visited the place. It was all weedy because he didn't weed it, but in the middle of the weeds, he found harvestable ginger. The soil still had that organism that causes the disease, but it wasn't in its virulence stage. When he applied the vermicompost, the microorganisms in the vermicompost took over the field and did not necessarily kill the pathogen, but made the population so low that it wasn't affecting the ginger much. It goes to show that application of vermicompost in the field is really not dependent on its nutritional quality and quantity, it's microbiology. I think that's a testament from my previous research, all 60 articles of it, that vermicompost’s power comes not from its nutrition, but from the microbiology.

Jesse: I was going to ask how many different studies you published on vermicompost.

Norman: I have about 60 articles, maybe 70, including abstracts and short articles, and about three books that talk about vermicompost and earthworms. One that I produced here in University of Hawaii Hilo is called Tea Time in the Tropics. I co-wrote it with a professor in the University of Hawaii at Manoa. It's downloadable, it's free, because it was commissioned and funded by the organization WSARE, or Western Sustainable Agriculture Research and Education. Another book is Vermiculture Technology, I co-edited it withRhonda Sherman and Clive Edwards. The other one that got published while I was in the Philippines was Biology and Ecology of Earthworms. It was more than 10 years in the making. Sadly, the year before I got it finished and published, Clive Edwards passed away. But it’s something that I'm very proud of, working with Clive, even though he was already gone, we were able to publish it finally. We thought it was not going to get published. But it was by grace that we were able to finish it during the pandemic and it got published finally.

Jesse: Taking some of your favorite studies or research projects, what specific benefits did you see? Was it more yield? Was it nutrient quality? Was it pest and disease resistance?

Norman: All that. We started with yield because our main interest for plants is whether it can grow and yield better than plants treated with chemical fertilizer. In almost all of our studies, we have a control plot where everything is chemically applied. All the rest of the plots have different rates of vermicompost application. For strawberries, we used the variety Chandler, and when we published it, some of the California growers called me at Ohio State and asked how it was possible that our yields are higher than what we produce here in California where we get the best strawberry yields. But I put it in perspective that these are small plots, and when you calculate for acreage, it's a projected yield. I assured her, “you guys are still the number one producer, but our plots show the potential of vermicompost.”

 One startling thing we found is that when you apply vermicompost into fields of strawberries, your strawberries will have a tendency to flower significantly earlier than those that are just treated with chemical fertilizer. When it flowers earlier, you also have more flowers in a cluster so you end up having more fruits. If you have bigger fruits, it means that your plants have the ability to produce photosynthates that are stored in their fruits. Photosynthesis are the role of the leaves. when you look at the leaves to measure the leaf area using a machine, you'll end up having bigger plants with more leaves. that explains why you have more fruits, because you have a plant that has a manufacturing capability to do more photosynthates and store it as fruits.

That’s what we saw above ground, the results of the application of vermicompost. If you look below the ground, what we found is that the microbial biomass of the soil that had vermicompost is significantly higher than that without vermicompost. As a result, you will also have nematodes. Nematodes come in four groups. The ones that we don't like are the plant parasitic nematodes that attack the vermicompost or attack any plants. We found that in all the vermicompost applied plots, plant parasitic nematodes are significantly lower than those in the chemically applied ones. The mechanism of that is when you apply vermicompost, it inoculates the soil with microbial biomass, but it doesn't necessarily kill plant parasitic nematodes. They're all there, but they're in a population where they're just not virulent at all. They're in a number where they don't attack. Their numbers are managed by other microorganisms that are provided by the application of vermicompost in the soil.

That seemed to be a very common thing that's happening with all the plants that we tested, the tomatoes and peppers. We worked with plant pathologists at Ohio State, and sure enough some of the diseases that we tested, fungal diseases that we intentionally inoculated onto plants, are actually controlled by just the application of extracts. There are no toxins in extract, so how does it diminish the growth of some diseases? When you do extracts, you are transferring what the quality of the vermicompost is. If vermicompost has microbial biomass, the act of extracting that into aqueous form means you extract not just the mineral nutrition, the hormones, but you also transfer the microbial biomass in. When you apply it onto the foliage of your plants as spray, it will fight with the causal microorganisms that cause diseases. When you apply it as a drench into the soil, it will also inoculate the soil, very similar to how the solid vermicompost can take over the biology of the soil and take care of what's causing the disease.

It also affected resistance to insects. We found that if you apply vermicompost in solid form or aqueous extracts as a drench, not necessarily a spray, you change the biology of the soil, but you also change the physiology of the plant. For example, the striped beetles introduced into a pumpkin seedling can devour it in less than an hour. But if you put that same striped beetle into the pumpkin seedling grown in vermicompost, it just stopped eating the plant. The plant changes its physiology and biochemical composition to be unpalatable for insects. it enhances its ability to suppress disease by itself. I think those are some of the mechanisms that we found on plants that had been applied with vermicompost either as a drench or as a foliar.

Jesse: Were the applications that you did in your trials liquid applications, or were you top dressing or digging vermicompost down into the soil?

Norman: Both. There are benefits to application of vermicompost as a solid because if you apply it as a solid into the soil, it tends to linger and the benefits are seen longer term. If you apply it as a liquid, it doesn't stay as long as the solid ones, because then the solid becomes a source of food for the microorganisms, more than liquid. Also, if you apply as liquid, the extraction is something that you have to be very careful of because it doesn't store long. Based on our studies, if you extract vermicompost teas, the microbiome mass population count stays really strong only for 24 hours, and it goes so low after that. You can prolong it up to seven days if you store it in a refrigerator, like 4° C. If you don’t refrigerate it, they're very active and they're very dependent on whatever nutrition is in the liquid. They utilize that and in about 24 hours, everything's gone. That's probably some research that we need to do, how to prolong it longer and use it longer than 24 hours.

Jesse: But we found that just doing an extract, just pulling them out into a liquid and not adding any oxygen, not adding any other ingredients, that does stay shelf stable for quite a bit longer. then most of our customers, they'll add microbial foods as they apply it so that the reproduction happens in the soil rather than in the liquid ahead of time.

Norman: Right. I heard some people add sugar. Of course they love sugar. The problem is that if you do have other microorganisms there, like E. coli, because sometimes when you have raw manure as a source of your vermicompost food, some manure could have E. coli and the danger of that is if you add sugar E. coli will spike up. That would be why producers are not adding anything, to get rid of danger of having spikes of unwanted microorganisms.

Jesse: Often they feed things that target fungi, like fish hydrolysate or kelp powder. Our customers will apply the extract as they're planting. The microbes, like you're saying, have to get established in the soil once they leave this material. But then the plants that they're supporting will feed them over the longer term. The plant will then become the source of the food and habitat for the microbes.

Norman: Yes, the liquid is not going to support the microbes as long as the solid. You apply it into the soil, then they're very dependent on what's in the soil. If the soil is already rich in organic matter, then they can persist longer. But if you're still building biology and organic matter in that soil, they may not be able to sustain the microbes for a longer period of time. That’s why in our experiments, we apply extracts every four weeks, or every eight weeks.

Jesse: If you were trying to improve the overall quality of your soil, you would probably start by doing more applications, but then over time that soil would improve to an annual application.

Norman: Yes. You'll taper off because you will achieve balance in your biology. There was a chapter in that Vermiculture Technology book, about a study in Australia where they were able to achieve that balance in a vineyard just through the application of vermicompost. They were achieving yields without application of anything for five years with just a single application of vermicompost.

Jesse: Wow, that's amazing. Based on what you learned over the years, what recommendations can you to make to growers? Let's start with producing vermicompost itself. Is that something that you’ve done a lot of? Do you have any recommendations?

Norman: Sure. There’s a household module and then there's large scale too. For households, all you need is a raised bin with holes in it. Worms need oxygen, so it has to be aerated, a nice bedding of say shredded paper, then make sure that the earthworms you collect are the ones that can live in captivity. Not all earthworms can do that. We have red wigglers, the Indian blues, about seven types of earthworms are good vermicomposting earthworms. They have to be able to live and reproduce in captivity, and they have to be surface dwellers. That means they're very dependent on what you feed them fresh, and then leave the bottom part already processed, So if you feed them slowly, they will chase the food up and then you harvest the bottom.

They have to be loyal to the bin, because there are earthworms that are highly social, that leave the bin. Indian blues, when they detect that it’s cold or it's hot, then they leave the bin and just leave you empty handed.

You have a bedding of shredded paper, you put your earthworms there, say red wigglers, and then feed them maybe weekly, inch by inch, taking care that the box doesn’t become thermophilic. Earthworms have to remain mesophilic, room temperature.

What we do here in the University of Hawaii, and what we recommend is to prepare the food stock. We have food waste here, we put it in a bucket after chopping it into small pieces, we add water and a source of carbon, which is paper. We soak the paper, and then we spread it on top, inch by inch. We don't water anymore, because that feed already has enough water to sustain the earthworms. Then we cover it very loosely with a dark material. You can even use black plastic, they will not suffocate if it's loosely put on top, and the reason for that is it mimics nighttime, because earthworms are nocturnal. If you don't have anything on top and it's bright, they stay at the bottom, and so are less productive. When it’s dark, they're active 24-7. You only feed them when the old feed already is turned into castings. Usually that happens in a week, so you don't feed them every day. Earthworms are not that fast feeders, so you harvest what's at the bottom, and you separate the worms, either manually or using a screen.

We have a large scale vermicomposter here from Michigan. We bought two from them, but we also have prototypes of those bins that we manufacture ourselves, we try to mimic what we got from Michigan. we use whatever we have in the university. We collect fruits that are dropping from the trees, and food waste from our cafeteria, and we use a lot of paper waste too. we prepare it the same way as we did the household bin, where we use shredded paper as our bedding, and we use red wigglers as our worms and we feed them every week, and we put black plastic on top.

Jesse: You must get a pretty good volume of castings then?

Norman: Yeah, we do, we allow our students to use it in their own research, in our classroom, and in the field too, and then we also use it in our hydroponics.

Natalie: I do have a quick question about the hydroponics, are you doing 100% chemistry or chemical-free hydroponics then with the worm castings?

Norman: No, just 50%. We did try using 100%, but it didn’t go anywhere. What happened is when you put 100% vermicompost, the liquid becomes anaerobic. The microbes multiply so much that you can even see the water bubbling, then it starts smelling like rotten eggs. They can replicate so easily in that water and it became toxic and unlivable for plants.

Jesse: Have you seen farmers then that are using vermicompost either as kind of a solid application or as a liquid application? I’m working with farmers that are doing it on a large scale and I'm curious what you've seen in the field?

Norman: From what I've seen in the field, they're using it as liquid, only because the production of vermicompost is kind of slow. One of the benefits of using it as a liquid is your vermicompost will go a long way. you’re using very little and then you produce lot of liquid in large quantity and it can be applied to large spaces. so that's the reason why they're using it more as a liquid than solid around here.

In the fields, they’re using it on ginger, and on flowers like anthuriums and orchids. The flower industry here is huge. In hydroponics, we're use it on lettuce. Hydroponically raised lettuce is popular in Hawaii because there are slugs here that carry a disease that affects your brain, so lettuce raised in soil is no longer attractive to consumers.

Breadfruit is also huge here, and there's all kinds of byproducts from breadfruit. When they process breadfruit, they want to either compost it or vermicompost it. There’s a movement toward processing organic wastes here into either compost or vermicompost. Here at the university, I think we are the first campus that actually recycles our own organic wastes into compost and vermicompost. Two streams, because we can’t handle everything just by vermicomposting. We combine them in the end to re-inoculate the microbiology into compost that was eradicated during the hot-composting process. In the end, we have a product that's has the microbiology that we need for the soil.

Natalie: Because you work with the compost and the vermicompost, what would you say is the biggest difference between the two?

Norman: The biggest difference is microbiology. When compost heats up, you eradicate many microorganisms that vermicomposting produces because it stays cool, it's mesophilic, and the earthworm gut process enhances that microbiology too.

Natalie: I'm curious, what's your experience on the earthworms eating and breaking down the chemicals and/or heavy metals that make their way into the foods.

Norman: That's a good question, because some of our raw materials, food waste, and especially animal waste may have heavy metals. Fortunately, earthworms are the cleaners of the earth. They have the ability to absorb some of the heavy metals into their fat tissues, so whatever is ingested is already free of heavy metals. We use our earthworms as sacrificial lambs to filter some of the toxicity in raw material. That's a good thing. The bad thing is if the earthworm dies, then it will release it back into the soil. Vermicomposters and all of us practicing sustainable agriculture have a responsibility to make sure that our soil is habitable for the earthworm so that we keep them living so they will not release back whatever they are carrying in their bodies as they clean up the soil.

Earthworms are used as cleaners of soil that is polluted with spills of chemicals. They usually introduce earthworms into that spill-polluted soil and then they dredge it. They collect the earthworms and then they burn the earthworms with heavy metals in them becuase if you leave the earthworms there, then you will release it back into the soil.

Jesse: If you were sourcing a vermicompost product, rather than making it yourself, what would you look for and how would you analyze it? Because there's lots of different products that you can find. We like to use the Soil Food Web methodology of analysis, just as a comparative guide between the different products. What are the kinds of things you're looking for, and how would you evaluate it?

Norman: I'd like to see a container that is breathable. If they come in a container that's sealed, then you may have killed all the microbes already. In Target there's a very nice worm poop for sale. It's very attractive, and probably you'd buy it, but the container is sealed, and it's probably just dirt

Then I check if it's moist to the touch, because the microbes in vermicompost require moisture to keep them alive. If it's dry as a bone, then forget about it. Then on the label, I would look at if there's a microbial assay about its active fungi, active bacteria. I don’t care about the nutrition because nutrition is already in there.

If it’s sterilized, forget about it. I have been contacted by companies that wanted to incorporate vermicompost in their products, who asked me how to sterilize it. I said, “You don't sterilize vermicompost. It will lose its power.” So they stopped calling, because there is a requirement that biological fertilizers that are shipped to the Hawaiian Islands need to be sterilized. That’s their problem. I think they lose their market here because of that.

Jesse: I’ve gotten to know Dr. Zach Jones, who does DNA sequencing of vermicompost products. A number of years ago he collected a bunch of different samples, all different feedstocks, all different methods. came up with a database that shows the same strains of beneficial bacteria highly represented across all samples. He concluded that there’s enough consistency between vermicompost samples, that wherever you're getting your vermicompost from, as long as it's viable, you can expect similar results. Would you agree with that conclusion based on what you've seen?

Norman: Yes. This is also consistent with studies we have done, that there are differences but they're not significant. There are signature microorganisms that are found in vermicompost, whatever source material you use. For example, take cow manure vermicompost, food waste vermicompost, and goat manure vermicompost. There are little differences between them, but they’re not that significant. I think that goes very well with the finding that signature microorganisms are the defining thing about vermicompost, even if they come from different sources. Some microbes thrive just as they are just because of the gut processes that happen during vermicomposting.

Jesse: Would the microbes cultivated in vermicompost be more soil-adaptable than the same microbes cultivated in a lab in an aqueous setting?

Norman: Yes. Some people ask, why vermicompost? We’ll just find these signature microbes inoculate them into the soil. But microbes are delicate, and if you raise them in a perfect laboratory environment, when you introduce them into a completely different environment in the soil, they may not survive. That’s one danger of introducing a microbe that didn't go through that vermicomposting process. Again, these microbes are there for a reason. They exist because of the combination of the earthworm’s action and all the other microorganisms associated with the earthworm action. If you separate them out of that system, then there’s a possibility that they may not even survive.

Going back to the tea we talked about earlier, the microbes don’t have anything to bank on. There's no reservoir, there's no home, there's no solid part they can attach themselves to if the environment is too harsh for them to survive. That's what happens with teas. When microbes aren’t raised in a system with earthworms and all the other microorganisms in the process of vermicomposting, they may not even survive.

Jesse: What is the best way of getting the message out? As you know, this is not well-known enough in agriculture. I'm quite impressed that you've landed in an environment where you're able to do all this stuff and that the campus and everything around you is on the same wavelength. But how can we better get the message out within agriculture more broadly?

Norman: I wish more people understood that vermicompost is not just fancy compost; it’s biologically active material with powerful benefits. We should have more farmer-led trials. Looking at visual evidence before and after is a powerful way to convince people to use and even produce vermicompost. Beyond that, we should have our policymakers some policies to support manufacturing vermicomposting or recycling waste. If our city council and our government support that, then consumers will have more demand for vermicompost or organically grown products, then our farmers will also be motivated.

I've always told our students that not all of you have a green thumb – some of you may kill more plants than you grow. So if you can’t grow plants, support those who can. For example, we produce vermicompost and compost on campus, but how do we let people see it? We turn our landscape into greens. We grow food around here. Our flower business that used to grow flowers, we turned it into a vegetable garden in front of the library where everybody will see it, not just from our class, but everyone passing by. Our gardens have become a focal point of the university, a focal point of our Earth Day celebrations here. We have K-12 students touring our gardens, and when they go back to their schools, they can start their own too. We see that ripple effect on school gardens that are popping up all over the place.