Sound Effect: 0:14

[music]

Jordan Powers: 0:15

Welcome to Cultivating Curiosity where we get down and dirty with the experts on all the ways science and agriculture touch our lives, from what we eat to how we live. I'm Jordan Powers.

Emily Cabrera: 0:27

And I'm Emily Cabrera. We're from the University of Georgia's College of Agricultural and Environmental Sciences.

Sound Effect: 0:34

[chime]

Jordan Powers: 0:35

Earlier this month, we celebrated International Compost Awareness Week, and we're gearing up for National Learn About Composting Day on May 29, which focuses on educating people about the benefits and processes of composting, a natural way to recycle organic waste and create valuable soil amendments. We're in the studio today with Josh Fuder and Laura Ney, Agriculture and Natural Resource Extension agents for Cherokee and Athens-Clark counties, respectively.

Emily Cabrera: 1:00

Josh, Laura, thanks so much for coming in today. Before we get into the nuts and bolts or the banana peels and coffee filters. What is compost?

Josh Fuder: 1:10

Compost is a valuable soil amendment; is the way I would use it as say, a gardener, a great form of slow release nutrients and a great way to add organic matter to our soil.

Emily Cabrera: 1:22

So you mentioned that this is an amendment. Can you get into that a little bit? Can I plant all of my spring and summer vegetables in compost?

Josh Fuder: 1:30

Yeah, I think that's a great question. And something we see in county offices all the time is folks will build the raised bed garden in the backyard, and it gets filled with essentially 100% compost, or, you know, something similar. And they will usually call us after that first half year or first year of unsuccessful gardening. You know, we've done enough testing with these folks over the years, and realize typically in those raised bed situations with just that, oftentimes the pH is quite high. I've tested some materials that are well above eight which on the pH scale, most vegetables don't want to be that high, and oftentimes the nutrients are still really, really high. Not to say that that was bad compost, but again, the goal of that material is really meant to be an amendment, couple inches tilled into, say, a mineral soil or a native soil, and then we're improving that native soil, both in South Georgia in sand, and in North Georgia in clay.

Laura Ney: 2:27

It's important to keep in mind too, that just because it looks like compost or is an amendment or looks like good dirt, what makes compost compost are the processes that we use to manage the waste that we're putting into those piles. And so, if we reach certain temperatures and get certain microbial communities activated, then the physical and chemical reactions happening to that product is what makes the really special end product, which we call compost.

Emily Cabrera: 2:51

It's alive.

Jordan Powers: 2:52

It's alive[laughter]. We were just talking about this the other day, and I love that the science of compost, because it is! I think it's easy to think, oh, I go to my local hardware store and I grab the bag. But realizing that there are so many processes that come there, and we will acknowledge, right off the bat for this episode that we are just barely scratching the surface of compost and the processes, and we will be sure to include a wealth of information and resources in the show notes for our listeners who may hear this and say, "Okay, now I want to know more. Let's dig deeper." In the meantime, we've all heard composting is a good thing, but why should someone consider taking on this endeavor?

Laura Ney: 3:27

It's interesting. You would think it's pretty straightforward. So, I always composted because I like gardening, and my obvious answer to that was, I want something really beneficial to put into my garden, and I never even thought about other reasons for composting. But as I've worked with the county and Extension role, and we've worked with Master Composters, I've learned a lot more about other reasons. So even if you don't have a garden, or you're not that interested in gardening, or you don't have space, there's great reasons to compost; one of which is just keeping organic material out of the landfill; and that can help your city or your municipality, because it's expensive to manage organic waste in the landfill. But also because organic waste in the landfill creates a lot of methane gas, which is a huge contributor to global warming and ozone depletion, is actually comes out of our landfills, and specifically the organic matter that we put into it. So by composting, if you care not at all about plants [laughter], you can actually be doing a little kind of mini blessing for the environment there.

Josh Fuder: 4:24

Maybe, a kind of pie in the sky reason that I enjoy composting is really I think about the global food system and the bananas and the coffee and the things that I eat or use. And then, you know, that may be something that was grown in another part of the world or another part of the country by people I'll never meet, and those are nutrients or sources of carbon that I now get to use, that grew something in California or Honduras or something like that. So that is something that in my composting at home, I do try to consider and think about too, is now I can grow, hopefully healthier plants with some of these sunlight, water and nutrients that came from somewhere else in the world.

Jordan Powers: 5:00

I love that so much [laughter].

Josh Fuder: 5:02

[laughter]

Jordan Powers: 5:02

I don't even have words for how much I love that. I mean really talking about global gardening.

Josh Fuder: 5:06

Yeah.

Jordan Powers: 5:06

Right here at home, which is really, that's really special.

Emily Cabrera: 5:09

So we've covered the what and why. Now let's get into how to compost. We know the amount of space listeners may have to take up composting will vary. Is there a composting method for everyone?

Josh Fuder: 5:20

I certainly believe there is. There's a lot of ways to compost, and there's a number of ways to kind of unsuccessfully compost, and that's kind of a journey I've gone on. And it took me, one adopting some worms about 10 years ago, and going to a training actually here in Athens. It was a multi day compost operation, like large scale composting, and we got to tour the Athens facility. And my world had changed after that; thought of it differently, because I was very much like a lot of composters, an organic trash heap. It wasn't really an involved process. It broke down, it decomposed, but it wasn't really composting. I mean, the goal with composting is, hopefully, we're making it faster. We're speeding up that decomposition process, or maybe making something that's a little bit higher quality that is usable, and not just, you know, stuff that still has pine cones in it. Sure it's decomposed organic matter, but it's probably not compost. So a lot of ways to compost worm bins to tumblers to just a heap. There's many ways, and I think there is something out there that can fit even for somebody with a small yard or even in an apartment or a school classroom.

Laura Ney: 6:33

Absolutely, I myself have also failed at composting many times, and a lot of times I'll just do my sort of lazy man's compost in the backyard, which is really just my decomposition pile, which is perfectly fine.

Josh Fuder: 6:45

Organic trash heap.

Laura Ney: 6:46

Yeah.

Josh Fuder: 6:47

Those are organic trash heap.

Laura Ney: 6:47

Okay.

Emily Cabrera: 6:47

[laughter]

Josh Fuder: 6:49

No judgment. Those are great.

Laura Ney: 6:49

We can talk a little bit later about maybe what the differences are between your end product doing that and doing compost. But in terms of how to compost, I have found that you can do a heap, but having some sort of wall or structure to keep that heap together can be really helpful. You'll notice that, especially as your pile breaks down, the heaps will get flatter and flatter and will spread out. And the problem with that is, an important part of composting is building up the temperature inside of your pile; and as your pile disperses and becomes flatter and doesn't have the cubic dimensions that it should, you can't build up that heat. And so whether or not you use chicken wire or cattle panel or some pallets or a few boards, you can use whatever you want, but having some walls or structures around your heap can be really helpful.

Josh Fuder: 7:34

And I would add multiple either bins for worms. Multiple bins outside is usually a good thing, so we have one that we're in that process, as Laura described, of building, and then hopefully we have one that's finishing, and maybe we're starting to use. That's one way I was failing, and I see it a lot in, you know, even community gardens and other places, is they have one big pile, and it's never at a stage where we're starting to actually maybe get to use and apply some of that compost. So I think one of the easier things is just maybe add a second bin or a third bin.

Emily Cabrera: 8:08

I will absolutely admit I have done this too, where I just kept adding and adding to the same pile, and did not think about having multiple piles, and I ended up with an organic trash heap that was also liquefying.

Jordan Powers: 8:21

Oh no.

Everyone: 8:21

[laughter]

Jordan Powers: 8:22

So having kind of that cyclical nature of one you can currently use, one you're currently feeding. And for those of our listeners who don't have space to do any of this, our friends over at UGArden actually have an amazing service that you can drop off your compost to them for free, so we will be sure to link that in the show notes as well, because for some of us, we may not have any space or the time or the energy or the interest, but we hope that listeners at least consider this as we kind of dive deeper. And if UGArden is kind of outside of your range, where it's easy enough or convenient enough to drop off, certainly check or google your local municipality or any private companies that might be in your area that offer similar services. Now let's pivot to the do's and don'ts of composting, right? We just heard I'm talking about a liquefied pile [laughter], so we certainly want to make sure that we're not doing that. I think we've all been there, that we've gone, "I don't know if we're supposed to throw this in, but here we go." So Josh, what are the kinds of things that we should make sure we're adding to our compost piles?

Josh Fuder: 9:16

A lot of this is dependent on if we have a contained system, say a tumbler or a nice, clean things on the market, like the plastic bins that might keep rodents, 'cause a lot of the rules that we say don't compost this is because, well, it may draw vermin or it may create a nuisance. Greens and browns are usually how we define compost ingredients. Either they are, say, at 25 to 1 carbon to nitrogen ratio, or they're above that, and they're a brown more of a carbon source. At our house, it's usually just the uncooked portions, the fruit skins, the bottom of the broccoli and things like that, coffee grounds, those are kind of the common ingredients that go into ours, egg shells and whatnot.

Laura Ney: 9:56

Like Josh said, like greens and browns is how you usually hear it if you're creating your own compost bin at home. That's just a really nice way of explaining stuff that has nitrogen, that's sort of the fuel of the composting process and the microbes, but then the carbon is the actual organic matter that we're composting, and the living things in the compost need a ratio like Josh was mentioning, and they need a specific ratio. So when we talk about doing maybe 1/3 greens or nitrogen heavy stuff and 2/3 browns, it's because we're trying to reach that kind of Goldilocks ratio for the microbes. And so if you hear about those recipes, we're just trying to get the ratio right for the living things that are eating all of that stuff and processing it. It's tricky when you say greens and browns,'cause our greens are in our greens are not all green, and our browns are brownish, usually, but banana peels not really green, but that would definitely be a green. A tomato is still considered our green. It's the wetter stuff. Typically, a fresher item would be considered a green, and an older kind of drier item would be a brown. So for instance, freshly cut grass would be a green because it still has all the nitrogen in it, but older leaves or grass clippings that have been sitting for a long time that are essentially straw, that would be a brown. In addition to just that general ratio of trying to make the pile happy. Then you also have to consider what you have around the house, and I guess we're kind of pivoting into our don'ts.

Jordan Powers: 11:12

I was just gonna say.

Laura Ney: 11:13

It's hard to talk about your do's without your don'ts. An easy way to think about, it is the raw stuff is typically good, and just don't get too complicated in your head. If it's cooked and coming off of your plate, you usually don't want that in your backyard compost. The municipal compost, they get really really hot, can handle that stuff. So Athens-Clark County is an example of that, where they accept everything besides feces and dead things and whatever, but like almost everything, because it gets so hot, but you're just not gonna reach those temperatures. And then there's safety issues and pest issues in your backyard bin that you don't wanna mess with. We also tend to stay away from the breads and the oils, and a lot of us have maybe chicken or rabbits or something, and they're excrement, for radio appropriate term [laughter] can be used, and those are great sources of nutrients for your compost. You just want to keep in mind, if you're ever doing an animal waste, there are kind of limits on what you want to use that compost on. I mean, it's great for ornamentals. Shouldn't be a problem if it's like a corn or something that's not really touching the ground directly, there aren't problems. But unless you're really good about monitoring your temperatures and things, it's advised totally you can use that compost, but don't use it on certain things that are going to come into ground contact, 'cause you just don't know if you're killing off the potential bacteria and things in there.

Josh Fuder: 12:33

And I think that's why a lot of folks end up being unsuccessful composters or more organic trash heapers. Again, no judgment. But it's when they have the volume of greens doesn't match when they might have the volume of browns, which is, for most people, fall leaves. We don't have a lot of extra greens or nitrogen source to blend with that higher carbon input, which is typically just fall leaves for most people in the backyard. It's once a year, they have a lot of browns, and then they don't really have all the kitchen scraps or the grass clippings to mix in and help break it down.

Laura Ney: 13:08

I think that's a top five barriers to successful compost is just having what you need for that ratio all at the same time. It's pretty easy to stockpile browns, because they don't go bad or really go anywhere. You can just literally have a pile of wood chips or fall leaves or grass clippings. It's really hard to stockpile the greens because they get gross. I've seen people they're interested in composting. They'll have their friends or neighbors collect their kitchen scraps, and then adding it all together can really make a difference.

Emily Cabrera: 13:37

All right, so now we know what to include, and maybe more importantly, what not to include. Do we set it and forget it?

Josh Fuder: 13:45

Not if we want to actually be composting.

Emily Cabrera: 13:48

[laughter] Okay.

Josh Fuder: 13:48

No, we would hopefully be turning it to maintain that heat, that thermophilic stage, if we truly built a batch, which ideally would be, you know, a critical mass of maybe about a yard, 3 ft× 3 ft × 3 ft. That's usually about what you need to hopefully reach temperature stages. And then, yes, we're very much involved. Every four or five days, hopefully, we're aerating or turning it somehow so that we can kind of maintain that critical temperature fully. Then we're sterilizing weed seeds, even pepper seeds and cantaloupe seeds, all the stuff that may be in there. Otherwise, you're going to be growing the best volunteer plants all across your landscape when you go to use this compost that should then hopefully be neutralizing of pathogens, but also, you know, seeds. Those thermophilic stages, ideally, would be in that 130 to 160 degree range. I've had a batch make it up to about 170, that's a little hot. At a certain stage, if it gets too hot, it can actually then sterilize your good bacteria that are doing the work. So, aeration hopefully will then bring that down, kind of cool, that powerhouse that's going on, generating all that heat. But even in the summertime, I'll have a pile that, I mean is hot to touch, and that's just the biological activity going on. Yeah, yeah. That is all based on having a good ratio, too, and moisture, right? Those bacteria live on films of water. So we usually want that material about like a rung out sponge.

Emily Cabrera: 15:15

So would there be any need to put shade over a compost pile if it's getting hot, or water it if it's getting too dry?

Laura Ney: 15:22

That's a great question. So the shade is not really necessary. Typically, it's not that it could get too hot, because we usually get it uncomfortably hot to the touch, so the sun's not a problem, and it could actually, in cooler weather, help you. Drying out could be potentially an issue, if we're not getting a lot of rain. If you have it under cover, it may stay moist longer. So it depends on what you're struggling.

Josh Fuder: 15:43

Or it may get too wet.

Laura Ney: 15:44

Yeah.

Josh Fuder: 15:44

If it doesn't have cover.

Laura Ney: 15:44

But it can get too wet.

Josh Fuder: 15:46

And then it could get gross.

Laura Ney: 15:48

So if you're you have a lot of rain, and your piles getting too wet, a cover could help you manage that moisture. If you know you're not getting out there and watering it and it's getting too dry, you may wanna have it rained on or give it some shade. It's sort of like anything else; depending on what you're struggling with, you can kind of troubleshoot with how you place it. The whole recipe for compost is, like a lot of things, it's gonna be those two, the carbon and nitrogen, which is sort of like the energy for the microbes. And then when we talk about moisture, you're also always really talking about oxygen as well. So you just need the carbon, nitrogen, some moisture, like will repeat the rung out sponge is a good sort of indicator you don't want it dripping out of your fist if you took a handful of it, 'cause that means it's saturated, so there's not enough air in it. And that can sometimes our piles turn into what we call like a goopy mess, and it can start to smell it's a really common troubleshooting issue, and it may have just gotten rained on too much, or there's not good drainage under where it is. Sometimes having it on like a little bit of a slope can help, because then excess water will run away from it, instead of just sitting under the pile, and then the turning introduces more of that oxygen as well. So the recipe is both complicated and really simple. It's just carbon, nitrogen, oxygen, water, and you just kind of play with it until you figure it out.

Jordan Powers: 17:04

It sounds like it is kind of a low risk for people who may be getting into it that don't need the compost for the survival of their plants or for their garden. It's kind of a low risk, fun way to experiment with the science of our soil.

Laura Ney: 17:17

Absolutely. In my opinion, going back to the question of, can you set it and forget it? Really, the answer is no. If you want to be composting, it is, by definition, a human-managed, like highly managed system. You are supposed to actively be composting it. It's not going to compost on its own. It'll decompose on its own, but you're not going to be reaching those temperatures. You're not going to have the physical and chemical reactions and properties going on within that organic matter if you're not turning it, which is introducing oxygen, which is essentially fanning the flames of the microbial activity they breathe, just like we do. So you're building populations as you get oxygen in there. You could also potentially be buffering too high of a temperature when you turn it, you're mixing in the outsides into the insides. So the turning and keeping an eye on the temperature to see what stage it's in, and if you should be turning more or less, is very important to composting, and it's fun. You're talking about banana peels. I mean, you know, if you mess it up, it's not a big deal, and it's definitely a cool scientific process, and to go from your kitchen scraps and then at the end of however many weeks or a few months, and to hold it in your hand and smell it and look at it and it's not the same thing is pretty cool.

Jordan Powers: 18:26

So we have dealt with our carbon and our nitrogen and our water and our oxygen, we've turned our compost. Now, can we throw it right into our garden beds? What's next?

Laura Ney: 18:36

I'm glad you asked that, and a lot of times we haven't even touched on one of the trickiest parts is maybe you're doing everything you're supposed to do with your compost pile, and it's looking great. But how do you know it's ready? If you have a thermometer, I would highly recommend, if you really want to get into this, you can get some pretty affordable compost thermometers; that would be a great way to go. If you don't have a thermometer, you can just kind of check on how hot or steamy the pile is when you turn it. You want to continue your turning process and getting up to that temperature that you want to get to until it just won't heat up anymore. And you know, if you've been heating it up, and it's not just because you've done something wrong, but it's been working well, and then it just kind of peters out, and it stops heating up as much. That's a sign that a lot of your material has been broken down and kind of transformed the way we want it to be. But even then, there's a process called curing, and I'm not gonna lie, it's sort of a mysterious concept. We've been heating up the pile and encouraging all of these, what are called thermophilic microbes, because they like high temperatures to do their job in the compost. But over years and years and years of people creating compost, we've realized that the curing phase is very important, and that's letting those normal temperature microbe populations recolonize the piles and continue to process it and do their own processes, and essentially, they just sort of even out the compost. Josh mentioned something called being hot, and that can be, if there's minerals and nitrogens in certain forms in the compost, it can be sometimes detrimental to planting directly into that. So they're just sort of finishing the process and breaking everything down to where it's stable, and that's called curing. And there's no exact time for that, but I would recommend, once your pile stops heating up, to leave it for at least several weeks of just letting it sit there and breathe and then using it.

Jordan Powers: 20:24

So that begs the question, we've talked about organic matter and those organic heaps and compost. What is the difference between compost and this decomposed organic matter we're talking about?

Laura Ney: 20:35

So most people don't ever think about this. So this is a fun question or thing to talk about this. A lot of people who use compost for years have never really thought about the difference. And it really sometimes it looks very similar, and both can have great effects on your garden and be good amendments. But when you get down into the sort of soil science of it, basically the composting process, one Josh mentioned, on a practical scale, is you're just getting it much faster. You're breaking that stuff down. I mean, you're talking about sometimes close to 10 times faster, as if you just left it to its own devices to break down. But in addition to that, you're transforming those really simple organic molecules where get just a tiny bit chemistry in here, but sugars and carbohydrates, like the things that we eat that would be in our plant refuse that we're putting in there. And you're transforming it with all those microbial communities, and even sometimes the actual physical heat, into really complex organic molecules. And the reason that matters is those molecules have all these cool functions in the soil where they don't just evaporate off of the surface of your garden when you till it, or when it's broken down further, it can hold on to nutrients, because it's a really complex molecule with all these little edges, just like our clays and things that can has buffering capacity to affect our pH and keep it in a stable range. It does all sorts of really cool things, just because those molecules have been turned into something much more complicated than they were when they went in the pile.

Jordan Powers: 21:57

That's so cool.[laughter]

Emily Cabrera: 21:59

I'm convinced this summer is gonna be hot compost summer.

Everyone: 22:03

[laughter]

Jordan Powers: 22:03

Hot compost summer. [laughter]

Everyone: 22:05

[laughter]

Jordan Powers: 22:05

But not too hot.[laughter]

Emily Cabrera: 22:06

Not too hot, not too hot.

Jordan Powers: 22:08

A complicated yet not an all around us, very fun process, a low risk thing for listeners to dive into. I've learned a ton. I know I've started a few failed compost piles or organic matter heaps, is what I'm now learning. I should have been calling.

Emily Cabrera: 22:23

Goopy messes.

Jordan Powers: 22:23

Goopy messes.

Laura Ney: 22:25

[laughter]

Jordan Powers: 22:25

We were so excited to have this conversation, hopefully get listeners a little snippet of how they can get started. As I mentioned earlier, we will absolutely include a ton of resources from UGA Cooperative Extension and beyond in the show notes, including an article that Laura wrote for our college on composting tips. And of course, we couldn't have you all in without putting a shameless plug in. If you have questions, find your local county Extension agent through UGA Cooperative Extension, and we'll put that link in the show notes. If you don't know who your local agent is. To find them, we have a great resource to do that, because they will happily point you in the right direction to get started on your own composting journey. But in the meantime, Laura, Josh, thank you so much for coming in today. We had a blast.

Laura Ney: 23:04

Thank you so much for having us.

Sound Effect: 23:06

[music]

Jordan Powers: 23:07

Thanks for listening to Cultivating Curiosity, a podcast produced by the UGA College of Agricultural and Environmental Sciences. A special thanks to Mason McClintock for our music and sound effects. Find more episodes wherever you get your podcasts.