Organic Fertilizers (YouTube)

Added: 2026-05-16

[00:00:00]hi everyone hope you're doing well hope you're staying healthy today we're going to talk about organic fertilizers that's a pretty big diverse field it's interesting I'm gonna cover a lot of stuff today so bear with me of course you can pause any time and go back and listen to it again which may be more helpful in the class I don't know anyways obviously organic fertilizers are important for organic farming it's a requirement you cannot use conventional fertilizers in organic farms it's a fact organic is definitely becoming more mainstream consumers are demanding it there's more and more of it around you can definitely get a higher price for your produce so farmers are business people if they can make more money doing something they're gonna do it that way because they've got to keep the bank happy there are definitely some challenges with organic fertilizer we're gonna get into that a little bit let's do it organic production requires certification and certification is a murky industry I've just got a smattering over here of different organizations that are around that will certify organic farming it is very confusing for organic farmers and a lot of organic farmers have opted to not even certified they just say look I'm organic take it or leave it there certainly are costs associated with certifying you have to pay for annual or quarterly inspections to maintain your certification so this the least stringent of all these is USDA the rules for being organic under that are pretty pretty slack I have a picture here of a farm in Bangladesh because I wanted to point out that a lot of countries our organic and have been for a very long time by necessity they don't have access to synthetic fertilizers and they're just doing the best they can with what they've got so in a sense you know maybe a lot of them have things figured out but you know let's see what we've got here one thing I want to clarify is what is organic versus what I call inorganic I don't want to get too lost here it's not supposed to be too complicated but basically anything that has carbon these seeds or carbons any molecule that has carbon in it is considered an organic molecule so that's where this term came from Organic versus inorganic it's been a little bit confusing for people organic fertilizers have carbon in them where synthetic or conventional or what I'm gonna call inorganic fertilizers have no carbon there's no C's here there's oxygen nitrogen oxygen and the KS of potassium so these are salts that we would feed to plants these are not organic molecules they are salts that we mined from the ground or make from petroleum so what is important to understand is that plants absorb in organic okay so plants don't absorb organic compounds not readily that is which means we're left with just these types of molecules that plants can feed on right magnesium ammonium nitrate potassium calcium phosphate and sulfate right it doesn't mean that do not that organic fertilizers do not contain inorganic molecules right but let's see what happens here so organic fertilizers are typically derived from dead plants and animals so there is some form of decay and that is what they are right so they're composed of some sort of the rotting plant or animal and inside that there is bacteria fungi all the stuff we talked about from composting protozoa to eat the bacteria and worms and all that stuff basically to release all the nutrients that we know the plants need this is a really interesting picture that helps you to see what happens in the soil with respect to nitrogen what I want you to get from this is that let's say there's a plant growing up here and it drops some leaves and they begin to compost and rot decomposers begin to work on the material and release nutrients right those nutrients are then broken down by bacteria we call these nitrifying bacteria and there's multiple stages where ultimately they produce nitrates which then the plant can use again this is when I talked about how tropical jungles are productive because they're cycling their nitrogen rapidly in the soil but when we clear it off and then plant a crop we are not producing a cycle because we harvest the entire plant take it away we're breaking the cycle so those soils become very deficient quickly you'll notice that there is a branch here where bacteria can denied Rifai and lose it to the atmosphere that typically happens when soils are too wet so if you're growing wet all the time a lot of your nitrogen actually gets converted to nitrogen gas and evaporates from the soil and you lose it so it's important to keep the correct moisture levels when you're growing crops that's why typically plants that are really wet go yellow because even if you're providing nitrogen it's quickly being converted back to nitrogen gas and evaporating from the soil so they are fancy circles I'll highlight what I just talked about why feed organically so why would we feed organically right so one of the things that we like to talk about is that it's a slow-release fertilizer that means it takes time it takes time to break down time to form those inorganic elements that come out of it when the bacteria do their heavy lifting work it can also reduce leaching right so when we just add straight salts to soil they can wash out the bottom whereas organic tends to be stuck in the soil because it's releasing slowly it doesn't mean that there's no leaching but it can definitely be reduced organic fertilizer will also improve the biology because you're putting food in the soil that feeds organisms so that you have a higher population of beneficial bacteria your soil is then going to become more productive and also encourages beneficial organisms that might actually prevent disease like fungi that will protect your roots or bacteria that will out-compete nutrients for bad bacteria that might infect your roots as well other advantages of organic fertilizers so we know that they improve the organic content because we're adding organic matter which also means our cation exchange capacity improves so our soil can hold more nutrients it will also increase the water holding capacity improve soil structure so that means reduces soil erosion in the spring if you've got organic matter helping to bind the material we already talked about greater microbial activity which means more improved conversion of nutrients and reduced leach right so because the nutrients are tied up in the organic matter that's stuck in the soil and the spring rains it may not run away as salts as easily and lastly I want to talk about mycorrhizae a little bit mycorrhizae are a type of fungi that are beneficial they're a fungus that infects roots by growing into them they actually fuse with the roots grow into the cells and have a very tight connection with their cellular level of basically the phloem where the sugars are so what happens then is the plant will give sugars to the fungus right and you're like well why is that that's maybe it's a parasite well not really it's a mutually beneficial relationship right so plants can only really give sugar that's the only thing they have to offer and the fungus takes the sugar in exchange for giving the plant water and nutrients and you might say to the you know why what's the benefit to the plan right they so they get some nutrients well typically if you have a root ball for a tree let's say it encompasses a 10 meter wide span with a micro Raizel Association you could probably increase that collection area to 30 meters that's how much further the fungus will reach to acquire more nutrients in more water right so typically plants that have mycorrhizal associations that's this our more drought tolerant and require fewer nutrients so they typically for example phosphorus which is a typically difficult one to get plants with mycorrhizae associations are less prone to phosphorus deficiencies basically you go anywhere in the forest and you look at what's going on you dig a shovel into the ground almost every plant has a fungal Association like a micro Z that's what makes the forest so productive you don't have little elves running around spreading fertilizer to keep everything productive you have a very very efficient system that's benefiting from all sorts of interactions this is just a diagram showing a root cell and the hyphy extending out from the root in here is these these tight joints where the fungus interacts with the the root taking away sugar and delivering water and phosphorus on the top here is a picture of grass or turf that has a mycorrhizae associated and one that does not and the plant is much healthier with the mycorrhizal association so these are definitely very very helpful associations there are some challenges though right that means that we cannot use fungicides so a lot of times people use fungicides actually kill the mycorrhizae and ruin that association which limits the crops ability to collect nutrients and water which means it relies more on you to provide nutrients and water okay let's go back to organic fertilizers they increase organic matter and cat and exchange capacity they increase water holding capacity they improve soil structure which means less erosion we get better aeration increase microbial activity and organic fertilizers will leach less somewhat less than conventional and then of course they're also because we're dealing with organic it's a lot easier to grow fungal populations in the soil disadvantages let's be honest there are some they require microbial activity to break them down right so just like in our composting lesson if you don't have the bacteria if you don't grow the bacteria you're not going to get composting so in with organic fertilizers if you're not growing the bacteria then you don't get nutrient conversion now that has some implications right one of the more obvious implications is from a food safety perspective right where we're trying to control the growth of bacteria especially ones that are dangerous and so we don't use any kind of soil sterilizers say for example you're doing field production of lettuce you might get bacteria in the field that you just can't get rid of without risking control killing off the bacteria that are mineralizing all your nutrients or in a hydroponic organic setting like we're doing at the college where we're growing cucumbers and hydroponic conditions with organic fertilizers and media we can't add anything to sterilize the water because it will kill the bacteria and then reduce the rate of nutrient mineralization so that means you need the correct temperature pH and moisture levels all the time and you're focusing more on the bacteria in the soil than you are on the plant so yes we need mineralization to break down the organic matter into nutrients and that can be slow right that's maybe a good thing maybe a bad thing some organic fertilizers are faster than others unfortunately a lot of organic fertilizers are slow and for some crops that grow very quickly getting the nutrients out fast enough can be a real challenge and that's where you need to pay close attention to what fertilizers you choose and their rate of mineralization yes and so it's kind of related to the speed could be that nutrients may not readily be available when plants need them this comes from mixing different fertilizers so say you take a slow organic fertilizer and a fast one let's say the fast one releases nitrogen and the slow one releases potassium that means that your pet initially your plant is going to lots of nitrogen but not have sufficient potassium until finally that nutrients starts to release so you may exhibit potassium symptoms early on in your crop so designing an organic fertilizer system requires careful selection fYI in our folder this week I have links to organic fertilizer spreadsheets and lists which discuss their rate of degradation or mineralization so if you really want to take this seriously you got to pay attention to that kind of information okay let's summarize where we are so far we've added cation exchange capacity in water holding capacity we need bacteria to mineralize right so we have to have good conditions in the soil it is a slow release the plant response is not always understood we need to consider the source right and why are we even talking about this well because probably a lot of organic agriculture is in the future going back to this disadvantages microbial activity right mineralization I talked about it taking time it is also temperature related so that's another thing to keep in mind right so in the cool spring conditions soils are obviously cold and bacteria is moving around more slowly and so mineralization takes even longer so you definitely need to be on top of that right so faster and warm weather slower and cool leaching again maybe maybe not hard to say but water will wash just about anything out of the soil I know for example manure we know leeches into rivers and not only did we get nitrogen loading but we get e coli loading from leaching let's look at some sources of fertilizers there's obviously manure which is a high nitrogen content high enough that sometimes it can burn remember manures not composted then there's compost which is low in nitrogen right and often need supplementation blood meal is an example of a high nitrogen this is a rapidly breaking down one so it releases nutrients quick again you can burn a crop with too much nitrogen with those feather meal is which is very slow and has the risk of heavy metals soybean meal is slow but it's toxic to some seedlings be very careful using it on young plants fish emulsion is all over the map it really depends on how its prepared who made it what fish it is definitely prone to leaching but whether it's fast or slow is really variable alfalfa meal is a rapid release type organic fertilizer which can get very hot so you want to keep it away from directly on top of your roots and then lastly we're going to look at bat guano which is the highest in nitrogen and the most available but it is also possible burn nutrient burn once you got it use it in small quantities and then seaweed kelp which is a real promising one for a nitrogen and potassium before we get into it I want to talk a little bit about lime because at the end of the day you'll see why lime is important there are three kinds of lime there's calcium carbonate right which is basically just calcium there is gypsum which is sulfur in calcium and then there's what's called dolomitic lime which has both calcium and magnesium in it calcium is a very difficult nutrient to get inorganic fertilizer programs as is magnesium and so often times organic fertilizer programs rely heavily on lime now technically lime is mined from the ground as a mineral I mean it's it's very abundant on the planet but you know in the strictest of terms really it shouldn't be used in our organic program but almost everyone who doesn't have enough lime in their soil really struggles to get the proper calcium nutrition so keep that in mind as you go through this bunch of fertilizers looking at a typical mix here this is a complete organic fertilizer mix it's got kelp meal in here there's bone meal in here there's dolomitic lime I just mentioned that there's soybean meal and then there's agricultural lime so there's two bits of line this has got calcium carbonate and gypsum in it so there's your calcium is coming from these two and then your NPK is coming from here and iron also is in your blood meal so you get your iron from that let's look at these so blood meal dried powdered blood from slaughterhouses very high in nitrogen because there's a lot of protein in it there's the percentages like 13 1.6 so basically it's essentially all nitrogen it has some trace elements particularly iron which is very helpful for a lot of organic programs we use this on our cucumbers at the college to help keep the leaves green enough to compete with our conventional fish emulsion this is partially decomposed pulverized fish usually large schools a very small fish that are not typically harvested the most common is something called a Manhattan fish very high in nitrogen and our Manhattan sorry usually the fish are pressed for the oils and then what's the oils are extracted and sold as food supplements like Oh what is it the beta something oils whatever those healthy ones are anyways that industry has a waste product and that's the fish parts that are left after pressing so typically phosphoric acid is added to the fish meal to help break it down and preserve it the bonus being that phosphoric acid is high in phosphorus which means that the plants get the phosphorus that they need which is another difficult nutrient to get so fish meal is often another way of finding a way to put phosphoric phosphorus into your nutrient program is it our organic well that's a tough question phosphoric acid is not made by organic means but these things are often buried to three steps in the process of making the fertilizer so it's less obvious manure one one one you know is there a lot of fertilizer no but it's readily available typically if it's composted there's not much left and a lot of the nutrients in manure are released over time right so we're talking about decomposers doing their work so you add the manure to your field there's an initial shot of nitrogen but the rest of the nutrients start to come out as it breaks down over the season feather meal this is a tricky one feather meal is made from chickens that have gone to the slaughter feathers are modified fingernails so you and I have fingernails and we have hair it's all made from the same molecule called keratin basically they shred the feathers and they have keratin and that eventually is broken down by bacteria to release the nitrogen that's in the protein one of the problems I have with this fertilizer is that we don't know how the chickens were grown chickens and chicken farms are usually dusted with an T miticides to keep them healthy they are fed all kinds of things and the dust gets in their feathers and it's not easy to clean so whatever is in there is in your feather meal and another problem is that human physiology shared by chickens we have livers that detoxify things we eat but heavy metals are not we're not able to process those so typically we store them in our fingernails in our hair if you've ever watched CSI and they talk about looking at hair analysis they can see where someone's from and their diet by looking at the metals in their hair and their fingernails so if we have a feather which is potentially concentrating heavy metals there's a health risk for long-term use in your soil so that's another one to be careful with alfalfa meal this is a very good fertilizer it's well balanced you see are two point five one one we actually use this in our organic cucumbers at the college it does need bacteria to mineralize right of course the one question you might have is where and how is the alfalfa grown some farmers spray alfalfa some tree their fields with herbicides between crops it really depends but there are probably more and more alfalfa growers out there that are not using as many chemicals the other thing is that there is transgenic alfalfa which means GMO so what's in there I don't know personally I'm okay with it all but maybe not all of you are soybean meal this is high in nitrogen look here 7 1 2 is fairly high high enough that it can burn a crop if over applied it is there's lots of examples of where soybean meal has proven to be inhibitory to seedlings germinating particularly lettuce and turnips so if you're starting your garden material you want to avoid soybean meal for the seedlings then of course just like alfalfa there is questions about where the soybean come from how was it grown and a lot of soybean is genetically modified so keep an eye on that if you're concerned again I'm not but you know in the organic world there's a full spectrum of where people where their expectations are cottonseed meal cottonseed meal is a very useful organic fertilizer primarily because it will acidify your soil remember trying to keep your micronutrients available means keeping the pH below 7 with a lot of organic fertilizers you don't have much control over soil pH so a lot of people growing crops that need the soil slightly more acidic rely heavily on these types of nutrients for example so you want to grow organic blueberries you definitely need to use cottonseed meal to keep the soil acidic enough for the blueberries to grow properly it is slow so that means you need some planning get it into the crop into the soils early on and at the right position relative to the roots as far as modern technology and organic fertilizer there's a lot of potential for algae meal these are algae ponds up here where there feeding wastewater into ponds that recirculate and they grow algae and the algae take the nutrients out of the wastewater and then you filter out the algae and press them to make meal it's actually two outputs one of the other outputs is oil you've probably heard of biodiesel right so there's a lot of interest in producing oil from algae using human and agricultural waste and then the by-product from pressing it is the meal which we can use as a great fertilizer look at that 731 not bad this is actually a greenhouse doing a proof-of-concept accelerated algae growth in glass plates trying to see if they can process waste in cities more quickly I think there's a really interesting future for this as far as fuel energy carbon capture and agricultural output there's really no downsides to this and what's encouraging is we've been doing algae trials in Arizona and Texas for many many years now so there's a lot of expertise what we what we need is for the oil price to go so expensive that these other ideas become much more viable and of course right now that's certainly not the case with oil being below $30 a barrel lastly fairly new a seaweed couple actually new and not new kelp has been around for a very long time if you know anyone who lives in the Maritimes historically people who had very little money could actually just go down to the beach and gather kelp and sell it as a fertilizer ingredient and they were paid by the pound it was not a glamorous job and people and they did it if they really had to but kelp has been around for a long time what's really interesting about it is it's actually higher in potassium than the other nutrients which makes it a very useful fertilizer for bumping potassium up especially if we're finishing those veggie crops it's in the middle between rapid and slow so it's a moderate release rate the only risk associated is maybe some sodium if it's not properly washed before its ground and turned into powder but the industry is pretty good at washing it off and and making it safe for crops guano bird and bat droppings very high in nitrogen and it releases very quickly there's very little work for bacteria to do to release the nitrogen guano was actually the world's major source of nitrogen for agriculture for a very long time there's an interesting history history about this if you go back to the 1800s off the coast of Peru there are a bunch of islands these are their names if it matters - you can't just bail a stress lobos Maccabi and one wanna pay islands anyways these are islands that are far enough out to sea that there's no real predators on them they're rocky but if you look carefully there they look like they're actually rock but most of it is actually bird dung the stuff is literally meters thick because of millions of years of birds flying they're landing to rest and pooping and then leaving and they left lots and lots of bird dung on the island and in the 1800's these are some pictures of ramparts just picture your wooden pirate ship type boat parking up against the island they literally hacked pieces of the island apart and put it in their cargo and shipped it around the world to sell to countries for their farmers at one time it was the most lucrative trade that could be put in ships more so than opium but when we figured out how to make fertilizers which was in the 1900s this industry started to fall apart but there are still ramparts on the islands if you happen to go by in a boat actually and of course organic growing is produced producing a new need for the guano because people are looking for nitrogen and that's a quick way to get it so there's ago there rocky islands with very little rainfall so the bird poop doesn't wash away and then there's limited predators which means millions of birds land they're all time and that adds up into hi thick piles bird done so why is this forest productive it's organic what's going on well we know there's nutrient cycling happening nothing's wasted its decomposed by bacteria and reused again we know now that there's also fungi in here it's hard to write with a mouse that are helping to distribute those nutrients efficiently between all the plants and keep it productive in an ideal world this is how we would farm but very difficult to maintain high productivity if you're at all interested in more organic stuff I've got some links here this is the Guelph organic conference and then this is a website to an organization called wolfing where you click on it and you can find organic farms where there are opportunities to work usually they're not paying positions but you get food and lodging covered it's a fantastic way to go see the world there's woofing opportunities all over the place Australia New Zealand South America Asia all over North America if you're looking for something to do this summer you don't have a job yet maybe now you won't make much money but you won't starve so try wolfing