Vermicast and Vermicast Tea. The worms that do vermicomposting are different than your true earthworms that come up when you have a heavy rain in your yard and you see the little piles of stuff where the earthworms come up. So, litter worms are worms that don’t live in the soil but they live at the interface between the soil and the leaf litter.
The upside. . . the value of vermicompost is really that it’s a very heavily microbial process. More so than regular compost, though microbes are involved with decomposition throughout. With vermicomposting you have microbes all throughout the material, on the skin of the worms, and in the gut of the worms. It’s a moist process, in the dark,and protected, typically so the quality of the compost that comes out of vermicomposting tends to be much higher than thermophillic or other types of compost. If you do thermophillic composting or other types of composting and you cure that material on the side in a dark area for a long period of time, you can get a comparable material.
The vermicast tea project
Nevertheless, vermicomposting is very high quality. One of the things we started back in 2006 was a vermicompost tea project. The vermicast tea is valuable because to make vermicompost, and you can ask anyone who has experience doing that, is challenging. It’s a pain in the butt to feed them. You’re ranching basically. So the product being produced is very high value but it’s also high cost if you pay yourself for your time and think about how much time and energy you’re putting into it. If you’re purchasing it commercially, you’re paying much more per pound than you would if you were buying something from one of our local composters that take green waste in. It’s expensive.
So a way to make a little go a long way is to extract all the good stuff. Much of the good stuff that promotes plant growth very rapidly with vermicompost is water extractable or water soluable. The nutrients, including some nitrate, organic acids that are produced, and then some of the biology as well all can be extracted. So making tea is a way to make a little bit of this high value stuff go a long way. Dr. Wang and her group, did a video that is linked to in the description of this video. You can see some of the strategies for use. This is a microbial extract and you can see some of the strategies to make vermicompost on a larger scale.
Another vermicomposting perspective
We have a vermicompost book called, “Tea Time in the Tropics”. It’s available online free. I’ll talk with you afterwards. Now I’ll turn it over to Dr. Archana Pant who did a lot of the vermicast tea as her PhD project and is continuing with vermicompost tea. I’ll let her talk a little bit from her perspective and then we’ll chat some more informally. As a part of my PhD work, I started with chicken manure-based vermicompost and food-wasted based vermicompost to make vermicast tea. We did experiments with different vermicompost tea extraction methods, different phases of vermicompost life.
Either it was cured or uncured. Or what was the ratio of vermicompost to water we should use for better results on the crops. We did a series of experiments on that. What we found in our work is that vermicast tea can be a supplemental source of nutrition for different vegetable crops. It doesn’t only increase the production but also the quality of crops in terms of nutrient quality. Basically I did the antioxidant activity, carotenoids, and total phenolics in the crops. These all were enhanced with the use of vermicast tea. We also tested the effect of vermicompost tea on soil biological properties.
Using vermicast tea
We saw the high microbial activity in soil after we used vermicompost tea. Also we found some plant growth hormone in vermicompost tea. This might be the cause to enhance the crop production.
So these are the works I did in my PhD and we are still working with the vermicompost tea as it is useful for insects, nematodes, and disease control. This is the further work that we have been doing not only for crop production. Now what we’ve found is that the cured vermicompost was good for crop production. The vermicompost cured for 2 to 4 months before we used it for making tea. We did different dilutions of vermicompost to water ratios to make the tea. The 1 to 10 ratio, I mean ten liters of water or 10 gallons of water with 1 part of compost is a good combination for the better plant growth and health.
We tested whether aeration is necessary or not. We could use the pump and power to clear the vermicompost tea or we can just make a tea with no aeration. On that process what we figure out is vermicompost tea can be prepared without the proper aeration, like here as you can see, we can mix the compost and water and then settle down and let it sit for 7 to 10 days to get the nutrient and microbial population extracted into the water. We didn’t get a completely anaerobic situation because we wanted the tea to not become anaerobic and we did not provide aeration for 7 days.
That tea also worked well, but the aeeration definitely helped to enhance the process because we could make vermicompost tea in just 12 to 24 hours if we use aeration. That was the intent. We did not want to worry about where to store and how to store for 7 – 10 days without letting that compost tea going anaerobic that could harbor the pathogenic microbes and other microbes. The aeration is definitely the best but the plant growth are equal. The aerobic conditions without aeration in the tea is also ok, This is the work we have done.
So if you have any questions. . . Question: Is it ok if my finished vermicompost dries out? Answer: Drying out is ok. What you want to avoid is having it get rock solid. What we’ve seen is we lose biological activity and you lose some nitrate. What we’ve done is we’ve had stuff stored for a long time and it shrinks and gets to a solid thing and it gets dry and crumbly and its hard to reabsorb water. We’ve looked at the quality and the quality is still high but you get a cure rate that goes like this with regard to nitrate which corresponds to a lot of other good stuff and then it drops which we suspect has to do with the water loss and then the subsequent loss of biological activity.
Question: So let the vermicompost cure for 3 months minimum? Answer: That’s what I would say, 3 to 4 months minimum, yes.
Then I see the big worms down in there. I have my regular blue worms and when it gets to the finishing I see the big. . I call them my finishing worms because when I see those, the Alabama Jumpers, in there it’s a different environment altogether. We talk about true earthworms and litter worms. Alabama Jumpers are kind of at that interface. They are considered true earthworms, but they live closer to the surface and so you’ll see them in loea (mature soil) and stuff like that. there the ones that are kind of right there and so you can keep them in bins, but they like more mature conditions. Also, about the rate of application?
Brewing 600 gallons
So I’m trying to brew enough to fill a 600 gallon tote so that’s the final product. Once you have the tea brewed do you dilute it? Typically we don’t. You use it straight? What they have here is a microbial product, but if this was compost tea. . . If you come over to the blue barrel. So this is a paint strainer. So even if you’re using a ten gallon bucket or whatever, you can use it like this.
This is a 5 gallon bucket that they rigged. This normally would be filled with water but we have it here. You can purchase these things. . . They use them to aerate sewage treatment plants. Yeah, better than an airstone. You can use an airstone too, but this one gives more. It depends on how serious you want to get about it. Airstones will work fine. The way we do it is we recommend 10 to 1 or 9 to 1 as in 10% by volume of vermicompost for max. . . if you want that buggah to go and you can use that straight.
Based on volume
That’s based on weight or volume? By volume. So 10 to 1 ratio would be a little too much for this system which is essentially a 50 gallon system and this is a 5 gallon bucket. So you would have it all the way to 5 gallons to here and you would have it like this and the paint strainer like this. Therefore you want to keep it up top. This is a. . . we recycle our paint strainers because we don’t get enough money so talk to your legislators. That’s it. For aeration, what we’ve seen is you can get away with just a couple hours or overnight. We do just to make sure you get everything out and what we’ve seen is that you will get some additional mineralization and some biological activity.
One of the things that we’ve found for us,at least for the way we do it, is that the biology in the tank is not nearly as important as the quality and biology in the compost. That’s the most thing, because people get caught up with all the additives and all the stuff. I’ve talked to folks who worry about the kind of pump you use and loose the hyphae. . . So having that real high quality compost is the most important thing and then having some aeration like this you do get additional mineralization and additional things happening. So if you do it overnight, that’s great. If you’re going to do it passive aeration style then it’s gotta go for a week and this is all in the book, Tea Time in the Tropics. It’s available online.
Use it straight
And that’s it. We’ll use it straight. That’s what we recommend. You can dilute it to inject it into an irrigation line so it becomes diluted but we put it out just how it is. We can apply it directly to plants and we don’t have an issue. As far as injecting, I was thinking about just blasting it with the pump? That’s fine, you can do that, too. We have the trash pump and you can even plug it in if you have an adapter on your truck. The only thing I would say is I would avoid using manure-based stuff if your going to cover foliage for something like lettuce. There’s SOPs and practices in the book that talks about that stuff.
As far as mixing. . . There’s so many products out there. Do you recommend having separate applications of each? That’s a good question. What we have found, if you’re going to mix, I would mix at the time of application. Because what we’ve found is that when you use fish and stuff, the bugs will do different things and I don’t think the science is out there yet to really. . . By combining stuff up front, you affect the. . . It does different things depending on what you’re putting in there. So if you have a product that you like like EM-1 or something like that, what we do is combine it at the end.
So we’ll take our fish and our seaweed and our tea and combine them at application. Then it all goes out together. But if you brew it all together, depending on the ratios, depending on what it is, different things can happen and we don’t know enough about it. Using them individually is good but you can put them together one time at application. Some people use molasses.The idea is that the bugs that are in here, the microbes, they want to increase the microbes. Most people nowadays don’t use molasses, typically,because what that does is that certain bacteria will out compete everything else.
So the idea is, we haven’t done work in this area and I haven’t done as much reading as I should to really speak conclusively, but in the industry the people are moving away from molasses, because molasses will get you this big spike in bacteria that may or may not be beneficial. It can tie up a lot of the free nitrogen that is in here that actually is associated with the benefits indirectly if not directly. So typically not molasses. They’ll use molasses to wake bugs up and things like that. If you have good quality compost I wouldn’t use much or any molasses in there. Our recommendation is that you don’t really need food. You don’t really need to add anything. That’s our recommendation.
If you start out with good compost. . . If you have compost that’s mediocre, put water on it, put a little extra nitrogen,put some bonemeal or manures and get it spiked and going active. Get the temperature up and get a nice. Cure it for a little while and then use that. Because you don’t have to use vermicompost. So it’s all about what you start with? Guaranteed.