163: Onsite Compost Production Using Vineyard Waste

Like with many projects on a sustainable farm, composting at Niner Wines Estates began with a problem; what could be done with all the pumice from the winemaking operations. Patrick Muran Winemaker at Niner Wine Estates started experimenting with thermal aerobic composting in 2016. With a 200-acre property, the farm has a diverse array of plant material coming from the restaurant garden, cover crops, and vineyards. Patrick explains how they turned a waste stream product into a valuable commodity including what temperature a compost pile must reach, what plant material to include, how to inoculate a new pile, and how long it takes to make top-quality compost.


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Craig Macmillan  0:00 

Our guest today is Patrick Moran, winemaker at Niner Wine Estates in Paso Robles, California. And today we're going to talk about composting. Welcome, Patrick.


Patrick Muran  0:07 

Thank you, Craig. Happy to be here. And to talk about some compost today.


Craig Macmillan  0:11 

Yes, we are. And in the spirit of full disclosure, I want to let everybody know that Patrick and I work together. So this is not the first time that we've talked about this. So I know about what we do. But we're gonna try to get into the details here and try not to forget anything. It's a really cool project that you, you kind of you founded. Correct. You kind of got this whole thing going, right?


Patrick Muran  0:31 

Yeah, it was birthed out of a problem of what do we do with all this pumice waste and ruin to kind of a passion project of figuring out how to unlock the keys and composting all this waste that we had?


Craig Macmillan  0:49 

So when did it start? How long have you been doing this?


Patrick Muran  0:52 

So this started late 2016, early 2017, we start building piles, Gosh, 5, 6 years now?


Craig Macmillan  1:01 

Yeah, in a minute. So the idea here was that you had a lot of waste that was coming in, or grape material that was coming in and you wanted to do something with it. What were you doing with it prior to accomplishing with it?


Patrick Muran  1:12 

I mean, I've been at this now, gosh, almost 24 years, you know, when I started, we had our big 40 yard roll off dumpsters getting dropped off and are filling them up with grape waste and pumice and stems and all that kind of stuff. But you know, we're scheduling trucks and paying for these trucks to be on the road and do all this material and material is getting stinky out there in the yard, flies are starting to fester, we had, you know, a similar problem here. Here I'm paying for a truck to come drop off this dumpster that's going to kind of make a mess and in our yard for weeks on end. And then pay to have that material removed. It was a kind of an, I love elegant solutions in this was elegant solution to a problem where we can turn a waste stream product into you know, a valuable commodity.


Craig Macmillan  2:04 

Did you have an experience with composting prior to that?


Patrick Muran  2:07 

No, not to the degree of what we're doing now. My notion of composting was probably like most people's it's like, oh, just chuck it in a in a black container or something in the yard and forget about it for six months and then come back later. And all of a sudden, it's it's all done. That was more or less my notion of what composting was. But when you're talking thermoaerobic composting, to the NOP like organic standards, it's a little bit of a different feel.


Craig Macmillan  2:36 

How did you educate yourself about this? This is interesting to me this is you went from zero to now 100.


Patrick Muran  2:41 

Yeah. With Cal Poly, actually Cal Poly had an extension program. And they brought in Dr. Elaine Ingham, and she did a seminar on composting, thermalaerobic composting in particular. And it just blew my mind like because I'm I'm microbiologist by by schooling, you know, I spent my year in college studying microbiology, and she was talking my jam, like she was talking all the biology in the soils. And in this compost that was promoting plant growth. So she she really kicked me off on this path. And, and so I just started educating myself on how to do it properly, and how to the biology and the ecology that supports your plant that you're trying to grow.


Craig Macmillan  3:33 

So did you already have a plan for what you were going to use this stuff for?


Patrick Muran  3:37 

No, I just knew if it was done properly, we could definitely use it all over the place. Like all of a sudden you've got this thing that can grow. But we did have a target because we have were growing grapes in a world. Our compost is going to help support the life that grapevines.


Craig Macmillan  3:56 

When you started, were you using just pomice or were you adding other material to it?


Patrick Muran  4:02 

No, I learned pretty early on that the more diversity of your ingredients that go into that compost pile, the more diversity you'll have as far as microorganisms, bacteria and fungi and protozoa and all these these different layers of of organisms. And I figured out pretty early on that we're going to need a diverse stream of sources to kind of hit our target.


Craig Macmillan  4:28 

And where did you source that stuff from? Was it from the property? Did you bring stuff in from the outside?


Patrick Muran  4:33 

Yeah, I mean, we've got over 200 acres here. So with a with a garden, cover crop growing, you know, we've got kind of a diverse array of materials, it was just a matter of collecting them your and making sure they're kind of staged and ready to go.


Craig Macmillan  4:54 

What's the timeframe from when you have let's say pomice from harvest until you have something that you can use?


Patrick Muran  4:59 

Yeah, so the ideal timeline for promised to complete product is about 60 days minimum is 15. But 60 days is the point of which you get that rich, organic material that's consumed all it's easy foods, and you get a little more diverse array of microorganisms in there.


Craig Macmillan  5:20 

Are you measuring the microorganisms? Are you sending samples out or something to get an idea of what's there?


Patrick Muran  5:26 

Yeah, we were doing both I do it here, or I was doing counts like bacterial counts, and, and fungal counts kind of fungal biomass and bacterial biomass. It's a little labor intensive. And after doing it enough times, you can kind of get a good sense of what the populations are, by easy look under a microscope, we are also sending out to an outfit called Earth Fort where they'll do the assessment for us, and then just kind of give us the results.


Craig Macmillan  5:56 

So is that how you know when it's done? Or is there other cues to you? You go, hey, all right, we're there now?


Patrick Muran  6:02 

Yeah, the cues that I use really are color temperature and and sort of the touch and feel of it all he can you get a sense of that digestion is complete, and you get into a form that really does look, I mean, it looks like 70%, dark cocoa chocolate bar, you know, hit that. And the whole pile has a very consistent makeup. So it's just there, you know.


Craig Macmillan  6:30 

So you mentioned easy foods, what would those maybe be in those are things that the microorganisms are consuming? Is that right?


Patrick Muran  6:37 

I would go back a step, I think of this is a lot like making wine, you know, you have the materials, you're starting kind of an inoculum, or a biomass that is going to grow, that's going to consume the nutrients that are available. You know, as a winemaker, there's a lot of parallels in composting as there is to making wine, you know, tank size or vessel size can inform you on how much heat will be generated and how fast fermentation may complete. Same goes for composting, the size of the compost pile will dictate kind of the thermal insulation that can take place. So you can kind of create a lot of thermal mass and a big pile. The next step is food. You know, we think of these two simple nitrogen compost, you think the carbon to nitrogen ratios. So again, nitrogen is your food source, those readily consumable foods, sugars, for example, really, you know, feed into the bacterial populations that just want an easy hit of sugar, and they go, so those are going to be the easy foods, the more complex foods, and it's again, similar to, to fermentation, you've got diammonium phosphate, you're now your DAP is like just putting gasoline on a fermentation. And you have more complex organic foods like for fermato or whatnot, yeast derived but they're much more complex or not as readily available, and they'll take longer to digest and release that energy. So then you got your food source. So I think carbon to nitrogen ratios, composting, I think of yeast to simple nitrogen and fermentation.


Craig Macmillan  8:23 

So you're using a lot of the same kind of conceptual ideas that you use for making wine for making compost, it's there's some similarities in terms of kind of functionality in your mind.


Patrick Muran  8:32 

And figuring out the proportions of those different components. And kind of the momentum, you know, that can be generated by it is really the key to unlocking a successful compost operation, as it would be with a successful fermentation operation too.


Craig Macmillan  8:50 

When I was first learning about this topic, there was like a recipe that you were supposed to kind of follow. And one of the elements there was manure, so you had to have manure in the mix doesn't sound like you're doing that because there's not cattle on site.


Patrick Muran  9:02 

That's right. And we've stayed away from manure for the moment because we'd like to use whatever's available on the property. And high nitrogen can come from other things other than manure, which includes things like alfalfa, all your nitrogen fixing plants, alfalfa, some clovers, but also seeds have a fairly high nitrogen content, just so happens to be got a lot of those coming out of these fermenters. So we use seeds as a high nitrogen component, they act a little differently because they're kind of a slow burn as opposed as opposed to a fast burn. They definitely will contribute to that heat to that energy release that temperature zone that you're trying to hit.


Craig Macmillan  9:49 

Do the seeds breakdown because I've seen pomice compost piles before where the seeds just didn't change. Do they break down for you?


Patrick Muran  9:56 

Yeah, they do break down they're not they're not fully in kind of destructured, you know, they're still like this funny shell, they almost look like a popcorn, they swell a little bit and kind of spilled some of their guts, but kind of the shell sort of remains of the seed. So they definitely have a different look and feel than when they started. But they do add a nice volume filling component, something like perlite or something like that, you know, they kind of fill, fill out the compost, make it a little fluff here.


Craig Macmillan  10:29 

So even though there's this material left behind actually has a role that actually does something for the way the pile behaves, and what it will do eventually, it sounds like. On the manure topic, we have a new aspect to the system, the ecosystem at Niner. And that's chickens. Have you thought about or are you using manure from the chickens?


Patrick Muran  10:48 

Not yet, just because we haven't needed to. This is what the beauty of this whole system is, you're getting rid of this waste as it is, you know, you're getting rid of garden waste, when you throw it in a green waste bin or you throw it in a, you know, a compost pile, we're getting rid of chicken manure as you clean up the chicken house and things of that nature. So you're collecting it, so why not use it. So all of these different streams are going to come into play in the chicken manure will come into play as well. It's just a matter of getting the material there staging it to making sure using using the right proportions at the right time, we just so happened to have worked out a formula with what we have currently. That's really nice and consistent. And chicken manure will change it a little bit. So we'll have to tweak it a little bit to get everything just right.


Craig Macmillan  11:38 

Another thing that I believe you've been bringing into the system is chipped grapevines, and also material from landscaping. Again, I was under the impression that things with high lignin did not compost very well. Have you started with that material? Or is are things happening? Are you looking at stuff what's happened in there?


Patrick Muran  11:54 

Yeah, so the high carbon source. So that's things like any sort of wood material, wood chips, hedgings anything that's going to have a lot of that cellulose hemicellulose. Like those really difficult to digest components, those can definitely be incorporated. And we like a nice proportion of those because they are great fungal foods, and we're trying to grow fungi as well on these compost piles. Those are a great source of fungal foods. And those do decompose, they take a little longer, we can give a little more time to the compost piles in terms of digestion, because you'll get that fungal push towards the latter half of composting. As they start speeding off of those partially digested woody components and high carbon sources.


Craig Macmillan  12:50 

Do you have to inoculate the piles?


Patrick Muran  12:52 

You can totally kick them off if you make compost teas. And so basically you take a finished pile, make some tea, and then use that tea to inoculate a new pile that's like Like imagine and throwing it in, it's really kick things off. The other way is to simply just take a finished compost pile and use a small amount as an inoculum. Like you would fermentation an inoculant you with the yeast and innoculate you with all the stuff that I've grown up with this previous pile to get you started right away, or like a native ferment and you can kind of sit around and wait for it to it's kind of naturally get some momentum, it takes a little longer certainly get that going as well.


Craig Macmillan  13:38 

What is your method here? So you're collecting material, and then you have to make it into a pile of some kind. And then you have to manage the pile? Right? So there's things like moisture and temperature, correct. What specifically are you doing to manage the pile? And specifically, what are you looking at in terms of the variables that tell you oh, I need to do this or that.


Patrick Muran  13:55 

To start wit we start with about four different streams of materials. We're starting with wood chips, or woody material, high carbon source, we're starting with green waste, which is anything that was cut green. So garden waste that was cut green, we even took grass clippings from you know, when they mow or around here as long as it was green. That's going to be one stream. The other stream is going to be rake. So anything that came out of destemers, it's going to kind of live in one vein. And then lastly, we're going to do the skins and seeds. So anything that came out of a fermentation tank that was fully fermented so they don't now we have our seed component. So we just treat each one of those streams as a different source. And we'll compose it's about 40% of woody material and we consider the rake is of woody material. So we'll go rake plus wood chips that's going to compose about 40% of the material. The green waste stream is going to be about 30% of that material. Okay, so that's going to be in those green waste, clippings and whatnot. And then lastly, we'll use the last 30% of the seed, and skin material, all the pumps that came out of tanks as a string. So we're going to take those components in those proportions and assemble it and kind of mix it up, we make windrows out of this, and they're roughly four feet tall, four to five feet tall, and about eight feet wide, we're gonna try and mix this as well as you can, and get moisture in there. Moisture is really the thing that sets this whole stage up to digest. I mean, you like any living organism, like you can't live without water, neither can these organisms. And moisture really is the key component to keeping that. We're going to try and strive for about 40% humidity or 40% moisture content. That's a touch and feel thing. Like you can really get scientific on how much moisture goes into a pile. But really, once you learn touching, feeling, squeezing the material, you'll get a sense of moisture, Woody materials really difficult to soak up. So we try and pre wet that a little bit. Seeds and green waste usually has sufficient moisture content to get things started. So mix it into a pile, mix it into those windrows. And then we no longer have covering piles at this point. So we just let them be out there. But if you have the right components in the right size, moisture, and composition, they'll kick off, I mean, we'll be up to 130 in gosh, within three days, certainly, we'll be right into a nice thermal compost, and then we're going to be turning it and we use a bucket on a tractor. It's not ideal. Ideally, you have a compost turner that aerated and really does a nice job of mixing. But we felt we got we can get by with a with a bucket on it on a tractor. And we do it by just simply folding that pile laterally. So if you think of a windrow, like pointing down, basically, one direction, we're going to come in perpendicular to that windrow, take kind of the outside piece, we're going to fold it up over the top, then we're going to kind of try and pull the core which is the hottest piece. And that's going to be become kind of the back end of that windrow. So you're kind of taking these in different sections. A better way to put it is if you think of a triangle, cut it into four parts. So you're going to have like the two wings, the top in the core. So you're trying to get the inside core cycled out, and you're trying to get the wings, whether it's the top or the outside sides to become the core, say you're just trying to fold union. So you're cycling the material through the core, that's basically the key. It is temperature and moisture determined. Typically were like every three to five days, but you'll find it needs more rigorous turning in the beginning. And then you can kind of back off towards the tail end.


Craig Macmillan  18:18 

When do you get the water in? And how do you do that? I've seen different solutions to that problem. What do you put it in? How do you do it?


Patrick Muran  18:25 

We've tried multiple solutions to this, the ideal is very small droplets. Like that's the ideal if you can get up a fine misting spray, that would be the best solution. Getting moisture in we use a fire hose, a water wagon. And that fire hose is able to emit you know a fine spray. So we go in with a water wagon, fire hose and a pump just basically wet out all the outside and then immediately turn it that's kind of the key is not set. It's just trial and error to figure out how much water do I apply? You know how what does this need to get? And that just has taken us a little bit of time to understand. You know, in the beginning it is more difficult to wet up. In the end. It's it's much easier to wet up knowing when and how much to apply is kind of that's what's taken us time to learn.


Craig Macmillan  19:21 

Yeah, practice. You mentioned temperature you mentioned 103 degrees Fahrenheit, what what are the temperature bounds? What do you have to hit? Why do you have to hit it? What's too hot? How often do you measure that? How do you measure it?


Patrick Muran  19:33 

temperature requirements are over 131. 131 to 170 for a minimum of 15 days. And you have to turn a minimum of five times in that 15 days. We use just a long stainless temperature probe. It's three feet, even a PVC sleeve and basically inserted into the core each day just to see where you stand. And then you're we do that kind of along the windrow in different spots, and kind of get an average of what's happening throughout the pile. And then secondly, we dig a little gopher holes into it like basically trying to dig down, or to get a sense of what the moisture content is like. And so we'll go dig through these piles, see where they stand, see what the moisture contents like, and then make a determination as to whether it needs water and turning and whatnot.


Craig Macmillan  20:31 

You just dig in there with your hand, you already have a tool?


Patrick Muran  20:35 

Now, I mean, it's it's, like I said, it's kind of nice. It's a touchy feely kind of thing. And you get a real good sense of what the moisture content and the different layers you can you'll find like moisture sort of will reside on the outside, but the core can become kind of dry, because that's the hottest spot. So just using your your old hands to kind of get in there is sufficient.


Craig Macmillan  21:04 

Oh, when I forgot ot ask, What do you been using the compost for? Where's the finished product been going?


Patrick Muran  21:09 

Right? Yeah, that's kind of going both into our garden or vegetable garden that we use for the restaurant and out in the vineyard. So they're applying it both aspects. And then I'm also making some compost tea or extract that I'm using to apply in the vineyard as well. The whole idea is, is really biology, you're trying to build the biology to support the plant that you're wanting to grow. And this is a great way to get the microorganisms that do the nutrient cycling and promote water holding capacity of the soil, suppress weeds. I mean, it's it's there's so many wins in the successful application of compost in those microorganisms to the soil. It's pretty cool stuff.


Craig Macmillan  21:57 

Are you measuring that to see if there's changes over the time? Like maybe you're doing some kind of trial or experiment?


Patrick Muran  22:03 

Yeah, yeah, we're working on on trying to assess this from a biological standpoint, what we're doing, what type of impact is that making? And how do you quantify that? There's a lot of discussion on that right now, what organisms matter what organisms don't matter? What is that nutrient cycling? Like? are you introducing harmful organisms to the, to the process? Yeah, we're trying to get answers both from a metabolic standpoint, just like metabolically, what's the activity in that soil, and then we're also doing it just by cell counts, and biological counts out there. Ultimately, we'd like to see long term what the impact is on the vine, as well. So we're trying to segment out different different blocks in our vineyard and assess what the yield is like what the cane weights are like what you know, the growth is like, and possibly even water holding capacity of the soil in the future.


Craig Macmillan  23:08 

What is the number one like challenge or obstacle that you've had to overcome with this whole program?


Patrick Muran  23:12 

It's like anything, just just getting off the ground, you know, like trying, failing, trying and failing. Doing it over and over again, it did take some time to get comfortable with like these types of assessments because I don't have like the analytical tools like to do it. So there is a little bit of a touch feel component. So just being comfortable going out there and saying, we need moisture, we need 200 gallons on this pile, you know, it needs to be turned today, you know, that sort of stuff, keeping things from going anaerobic is is really key that promotes a loss of nutrients, organisms that that are not going to help your plan all these things and keeping things in an aerobic manner on that aerobic side is, is very important as well. So it's just trial and error and getting those compositions moisture and size.


Craig Macmillan  24:11 

That sounds like patience is an important part of this little in the willingness to keep trying, which I think is an important.


Patrick Muran  24:17 

Wine making should be a good base of knowledge because it's also an act of patience. You know, these these compost piles will take a couple of months. I mean, fermentations and aging takes a couple of years.


Craig Macmillan  24:30 

I do love the overlap. I've never thought of it this way. But I really do love the love the idea that the kind of the training and experience in one field can apply to another than some of the same kind of concepts in terms of like, hey, I have something that's alive, and I need to keep it alive. And I need to be patient as it does its thing. It reminds me of like a sluggish fermat you just have faith. You're gonna get through it. You know, just keep keep trying and try different things. Is there one piece of advice that you'd give someone who to start producing compost on site, either at the vineyard or the winery.


Patrick Muran  25:03 

Yeah, I mean, I, my advice would really be just to start, like just getting a sense of even a small pile, like something you can manage and screw up and not have much consequence, just start small. It will help inform you on, like how you can shift the dynamic, based upon what you add to it, you know how much moisture it takes to kind of get this thing together. And then also recognize when you scale, things are going to change a little bit, because the size is going to change and the whole, the whole dynamic is going to change when to scale to like a windrow size. Just as get started, like we started with wire, mesh kind of hardware cloth piles built on pallets basically and, and just learn from it. And it was a bit of work. But I mean, you could do a really small one in in the yard, just to get a sense of it, keeping it aerobic learning the kind of the warning signs of when things go anaerobic, keeping consistent moisture content, that kind of stuff, you'll know if you got it right, or you got it wrong. I mean, it's, it's pretty apparent. And we and we screwed plenty up and re composted, um, you know, a few times over each time you learn a little bit from the process.


Craig Macmillan  26:22 

Where can people find out more about you and more about what you do.


Patrick Muran  26:25 

I mean, as far as education goes, I would really reach out to either Davis or Cal Poly, find out what they're doing, they'll give you a nice baseline where to start, and maybe the education that can help you not learn the hard way, I would really go to those groups first. Obviously, there's a lot of online type of stuff. And this is this is a dangerous thing. So I would really pick maybe some organic standards, there's some good worksheets on making organic compost put out by the NOP like National Organic Standards and, and things of that nature, that would be a good place to start. Because you could go down a YouTube rabbit hole with thermal composting and the different ways I think that was my struggle to begin with was the subjectivity it became a subjective form. And it's like, wow, no, I think that there's a little more, there's a little more precision here that than just again, throwing it in a bucket and leaving it for six months. And coming back, there is a little more science to it.


Craig Macmillan  27:30 

And I do want to underline that there is so much so much more information and much higher quality information than there wasn't even 10 years ago. And so there's a lot of resources out there. And I think you're right, you have to be selective and decide what stuff is useful. And going to folks that have you know, the background and the science behind it. And there's a lot of that there. And so that's, I think we're living in what's going to become a golden age of composting here. There's more and more people do it. And there's more and more experienced this more and more ways of trying it. I think that's really exciting. And I really compliment you for the work that you've put in and sticking with it because like you said, you have to be patient and you have to try things and you're gonna fail and you have to just keep going. That's how you learn. You know, you gotta you gotta crawl before you walk, walk before you run. But that's our time for today. Our guest today was Patrick Muran, winemaker at Niner Wine Estates where he's been composting material on site for quite a while now has learned a ton and I really appreciate you being on the podcast, Patrick.


Patrick Muran  28:22 

Absolutely. Craig happy to happy to be here and happy to be supportive of anybody out there trying this and want to reach out to me do whatever I can to help steer you out of the potholes.


Craig Macmillan  28:35 

Well, we will have a lot of information also on the end links on the site. So there's a lot of resources out there.


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