Is Bat Guano a Sustainable & Environmentally Friendly Fertilizer?


Many of us who choose to grow organically do so, at least in part, because we want to grow in a way that is sustainable and more environmentally friendly. But just because a product is certified organic, doesn’t mean its use is sustainable or good for the environment. One such product I would personally not use is bat guano. Today I’ll talk about why. What is bat guano? It is simply bat droppings that have accumulated and decomposed over a very long period of time in bat caves. These aged droppings are then mined from the caves and used as fertilizer. Insect eating bats produce high nitrogen guano while bats that eat fruit produce guano that is high in phosphorus. Both types of guano are excellent fertilizers when used to address actual deficiencies. Bat guano also contains micronutrients and fresh guano contains beneficial microbes. Now let’s look at high phosphorus bat guano, which is produced by fruit eating bats. Organic gardens that are amended annually with compost probably won’t have a phosphorus deficiency, so I wouldn’t use a high phosphorus fertilizer, unless a soil test showed an actual deficiency. Adding more phosphorus than needed won’t stimulate blooms or produce sweeter fruit, but it can contribute to water pollution, inhibit mycorrhizal associations, and create nutrient deficiencies by preventing plants from absorbing other nutrients. So, unless there is a known phosphorus deficiency, it is a good idea to avoid fertilizers with a high “P” value in the “NPK” ratio. Even when there is a deficiency, there are alternatives that are more sustainable and environmentally friendly than bat guano. High nitrogen bat guano produced by insect eating bats, on the other hand, is more likely to be useful in an organic garden. This is because nitrogen moves through the soil more quickly than phosphorus, so there is more likely to be a nitrogen deficiency than a phosphorus deficiency. Even so, I wouldn’t use bat guano because there are alternatives that are more sustainable and better for the environment. I’ll elaborate more on this point later. Bat guano is also sought after because of its micronutrients and beneficial microbes. However, nutrients and beneficial microbes are available everywhere, and there is no reason to go to exotic locations like bat caves to find them. I’m also very skeptical that these products have anywhere near the diversity of beneficial microbes that you can find in good homemade compost. Why? Because there is a very good chance that the microbes in bat guano are dead on arrival when they reach your door. Think of it this way; how likely is it that microves that have evolved to thrive in a cave would survive the extreme and foreign conditions encountered in processing, packaging, shipping, and storage? Temperature extremes alone could kill them. If you want to add nutrients and beneficial microbes to your soil, it’s hard to beat homemade compost. No let’s consider the sustainability of bat guano. Bat droppings become bat guano after accumulating, decomposing, and aging in bat caves over a long period of time – sometimes decades, sometimes centuries. Guano beetles and microbes play an important role in this transformation. This very long aging process is often featured in bat guano marketing. In fact, some companies boast that their guano comes from ancient bat guano deposits. The downside of this very long process is that bat guano is not a rapidly renewable resource. As a result, if it is harvested for worldwide widespread use, it clearly is not sustainable. Harvesting bat guano also has a negative impact on the environment. Fragile ecosystems have developed inside bat caves that are entirely dependent on guano as the main energy input from the outside world. Many unique species have evolved in bat caves and and depend on guano as a food source. And some of these species exist only in specific caves. Harvesting guano threatens these fragile ecosystems and species. But the greatest damage caused by harvesting guano is to the bat colonies themselves. Bats are highly vulnerable to regular disturbances, which can disrupt feeding, roosting, and reproduction and lead to starvation, loss of pups, abandonment of caves, and even loss of bat species. Research in Jamaica has found that mining bat guano is the greatest threat to bat caves on the island and directly responsible for the loss of bat species and other organisms dependent on fragile bat cave ecosystems. This discussion is not complete without talking about the important role bats play in the environment. In addition to supporting bat cave ecosystems, it is estimated that bats provide billions of dollars in ecosystem services, including seed dispersal, pollination, and insect control. Their role in insect control is vital to human and animal health and to agriculture. They reduce populations of insects that spread disease and pests that damage agricultural crops. Given pressures already faced by bat populations, including white nose syndrome, which killed 5.7 million bats in North America in 2012 alone, I personally would not recommend a product that potentially further puts bats at risk. While bat guano is a very good fertilizer, there are other alternatives that are more sustainable and better for the environment. And there is no reason to go to exotic locations like bat caves in search of beneficial microbes and nutrients. Though our soil currently has nutrient surpluses, if a soil test showed deficiencies, I’d first turn to nitrogen fixing cover crops and compost and mulch from free local resources. If further fertilzation was required, I would turn to sustainable organic fertilizers like alfalfa meal, cottonseed meal, soybean meal, and livestock manures. I would do my best to avoid mined products, and I would definitely avoid bat guano. So, just because a product is certified organic does not mean its use is sustainable or good for the environment. In the future, I hope to take a closer look at more organic products that I would avoid for these reasons. As I’ve said before, nitrogen fixing cover crops and compost and mulch from free local resources are a great way to start building your soil, and over time you might discover that you do not need anything else. Well, that’s all for now. Thank you very much for watching, and until next time remember you can change the world one yard at a time.

69 thoughts on “Is Bat Guano a Sustainable & Environmentally Friendly Fertilizer?

  1. We talked about that word "Organic". Glad to see you educating the masses about why Organic isn't necessarily good!

  2. Good video. The sheer fact that bat guano (for me) would be imported from a very long way away puts me off using it in my garden.

    Besides, I have chickens who make plenty of poo to amend my compost pile(s).

    Patrick, have you thought about keeping chickens at all?

  3. Good point. I love bats and hate mosquitos. I have never been able to find bat guano in the store only online. Now I won't buy it even if I find it. But I don't buy any fertilizers or pesticides mostly to keep my garden budget down. I have 9 cubic yard compost bin.

  4. I have been watching your shows for about two years now, picking up tips here and there, but after your revelation about how your use of organic practices have resulted in a surplus of nutients, I have been paying more attention as it highlighted something I had been worried about for some time: People using 'organic' products simply because they are organic and not stopping to think if they are really needed. This video furthers that and shows, as I have also believed, that just because something is organic, doesn't mean it is sustainable or good for the planet.

    Personally, I had not heard of bat guano products, but I had heard of people with bat houses using the guano waste in their compost piles. I think in this sort of scenario, it would have less impact on the environment since a bat house isn't the same as an enclosed ecosystem like a cave. Plus, you don't have to wait as long for it to break down as the compost accelerates the process, but I would still question if it is even necessary to begin with.

  5. I seen how they mined for it once. they blow a big hole in the sides of the cave and the bats never return. plus it's roach guano.

  6. Agreed with all of the energy and transport costs the damage to the local ecosystems. It is just not worth it when you have free and local resources that can do the job while diverting materials from landfill.

  7. Although i find it hard to gather enough compostable material at the moment, i've never felt the need to buy large ammounts of organic material outside the garden. I watch what a bed does, it's water holding capacity, from the weeds in the spring i can already see if they have enough nutrients or not and then i add compost where needed and dry cow manure pellets and if that still doesn't work well enough, a handfull of inorganic fertillizers, but always as a last resort. I don't get massive yields or anything, but i can see my beds doing better and better each year and i try to learn from my mistakes. I just basically eyeball it. I know from experience and from what grows in the wild and where, what weeds prefer what conditions. Weeds are not only a problem, they are also important indicator plants. Love your greenhouse, such a good build!

  8. Man this guys channel has really gone down hill first bashing compost tea now guano this guy doesn't know much. time to unsubscribe.

  9. I dont know if its the same, but my bat house(4 chamber) is close to my compost pile. Every now and then I rake the ground below it and throw what I get into the pile.

  10. It's poop, bat poop, if you want poop, find a domesticated, organic source of poop. Leave the bats alone. Kinda what he's saying there Immortal. We might not all agree on seperate elements of someones gardening style, but you must admit, if you look at Patrick's garden, he's doing something right and he wants to narrow it down to a sort of no nonsense type of gardening that is A: less time consuming and B: less stressful on the environment. I like that kind of thinking. C'mon, stick with us 😀

  11. Thanks Patrick. As usual, a well thought through and well presented topic! I have to say that I was just beginning to think I wouldn't see your four footed partner in this one!

  12. Great vid. the first few lines is how I have been trying to word that. So thanks. I make points like this about peat. Please do one of these about peat. I apreiate the debunk , hey when you think about, aspect of where your vids are going.

  13. Very nice video. Good info. I'm not into using manures, but if i were to use it, i would prefer manure from organic plant eating animals. I don't remember seeing bat guano in stores, so it's not a choice for me anyways. Oscar is happy there is no bat guano in your garden, he checked it out.

  14. So interesting to listen to this video. Thank you for educating me, Patrick. THINK SPRING my friend. Headed for a 'cold spell' again. :0(

  15. Another great video! I spent a great deal of my youth and early adulthood spelunking. While I"m sure commercially available guano is processed and treated, every time I hear the words bat guano, automatically I think of rancid, ammonia stench and histoplasmosis. Bat guano in the garden is something we've never considered.

  16. A lot of food for thought there ! Luckily we have no access to bat guano or any of the organic fertilisers available in the US. Most organic growers rely on cow manure ,neem, castor cakes, ground nut cakes and other locally available resources as fertiliser.

  17. I really miss watching the sky fill with our little resident bats at dusk like they did when I was a kid. The ancient, hollow cypress trees that would house hundreds each, maybe some into the thousands, may have a little cluster of bats here and there hanging on for dear life.

  18. Well said! Is horse poo or chicken manure not sexy anymore? And of course, most of the time compost is all that is required for a backyard garden. Cheers Patrick 🙂

  19. I don't think adding too much p will prevent the plants from taking up other nutrients. that is the premise of the base cation saturation radio which has been proven to be incorrect as a way to manage soil nutrition. if you have enough of an element, adding more will have no positive effect.

  20. Hi, thanks for the video. Being that you are from the Chicagoland area I was hoping you can mention some other youtubers that may be in the same area/ zone. Thank in advance for your help.

  21. Thanks for pointing out that just because something is labeled as organic that doesn't mean it's sustainable or necessarily good for the environment. I've been watching your videos for awhile now and love them. It's true; we can change the world for the better one yard at a time.

  22. thank you again, I have seen these products in garden centers. always appreciate your information which saves us money.

  23. Here in the dirty south, red clay is dominate. But in the raised beds, its a combo of cow manure, compost, sand, and peat.

    Luv your page and the detailed narrations. Thank you!

  24. I am always surprised by what people will use in their gardens, almost solely because of that label. I mean…whatever happened to using bunny or horse poo? Most people can find someone who has pet rabbits and ask them to save the poo (or if the rabbits are outside, as if you can come and "harvest" yourself). If you provide them a small, lidded trash can for the purpose, they will be more than happy to oblige!

  25. Outsourcing is a last resort for me, and buying bat poo has never even crossed my mind lol. Thanks for sharing! 🙂

  26. As a nucense wild animal remover in Kentucky. I do a lot of a.d.c. work. I like using natural things to remove the animal. I use bats as an insect remover. I have heard some of my customers tell me they collect the poo from under there bat houses and compost it for two to three years then put it in the orcherd and the garden. I love using natural products cause they work. And predation is the best for insects.

  27. Nice one Patrick! I have to admit that I think of bats as being, like my house mate, not the most pleasant looking of creatures but appreciate they have their place in this wonderful world in which we all live together. You really have done your bit to educate people about the subject of bat shit in this short video clip and should be applauded! I ruptured my lower back whilst digging out a compost heap on Sunday morning. Does this spell the end of my contribution to the permacutlure revolution?

  28. interesting…i was at an island in peru that was preserved just for animals…it was full of birds, mostly seabirds. anyway, thay said they go in twice a year for cleaning and to collect poop for birdmguano. i guess its a major export. it smelled horrendous!

  29. Hi Patrick, Some great points in this video. I think that the more local resource the better, before oil people were growing veggies across the world using local resource only. These days we already have globally available products like for example coffee and bananas which are good source of nutrients for plants. I don't see point in using more exotic fertilizers like bat guano.

  30. I use my chickens and ducks dropping from my poultry to enrich my compost.  I feel good knowing that my chickens and ducks are free range, often times fed with surplus of what grows in my garden and forage around my land.  We do not use pesticide and treat our lawn with chemical fertilizer.  I just cannot imagine buying bat guano, if I must, I'll consider composted local cow and horse manure.  Thanks, very informative.

  31. thanks for the info. Lots of Mexican freetailed bats in Texas. got rid of my bat house attached to my home. Getting too many bats and they scare me at night fluttering around. They are definitely a tourist attraction here in Central Texas. One colony has 21 million, another 3 million, some small colonies roost under bridges in downtown Austin and San Antonio. Very popular little critters!

  32. Excellent video! Good homemade compost, worm casting and mulch provide all that my soil needs according to soil tests. Not that I would ever consider putting these amazing little creatures at risk anyway, regardless of the outcome of the soil tests as there are other sustainable sources non-invasive to nature and much closer to home that would readily supply anything my soil might ever be lacking. Cheers!

  33. While I have used guano products before, I generally look at these products as a temporary jump start only and even then only for highly degraded land taken out of production due to harsh chemical dependant conventional agriculture. In my opinion relying on them on a yearly basis is no better than chemical inputs. They will give you a good jump start though. After that it takes understanding biological cycles to not need further inputs.

  34. Thanks so much for raising awareness…. Everything is connected..yes yes and yes. Thanks for all the love you put in your videos. love love love. Baba Bear

  35. I have been trying to compost much like you do in your geo bins (with leaves and kitchen scraps). After almost three months there has not really been much progress. Any clue on what I could be doing wrong?

  36. Locally acquired resources are the best. Bat guano cannot be considered local.
    Viable bat colonies are a much more valuable resource than their guano.

  37. One yard– I have watched many of your vids and enjoyed them but on this one I have a difference of agreement with you my friend. I cant say much about bat guano, but what I decided to try is peruvian seabird guano with an NPK of 12-11-2. On my simple overwintered cuttings which are in pots Im seeing a boom in flowering in which my lower jaw has dropped considerably never before seeing this from a cutting. As for how it might affect my gardens I cannot say ,,, yet.

  38. Insect eating bats live under a bridge 1/2 mile from my house. I can collect several cups of fresh bat poop in just a few minutes!

  39. I always find it amusing (in a smug kind of way) to see what people are willing to buy to add to their soil, when they have bags of leaves, sticks and grass clippings ready to go to the city dump. Thanks for educating and informing.

  40. We have insect-eating bats. What should be done with the accumulating guano? We're concerned it (in a very non-exotic location!) will drain into one of our natural (nearly year round) creeks, located only 25'-30' downhill, due to all the rain. Any advise would be greatly appreciated. Thank you!

  41. Very informative, I have a thesis proposal with this bat guano and the crop is the celery, I really appreciate the information.

  42. Bat guano would be more sustainable, environmentally, friendly, and cheaper if you build a bat box for the insect eating bat to live in and a bucket for the droppings to fall in to.

  43. I love watching your videos and get a lot out of them. I wanted to check what your thoughts were about constructing a bat house in the backyard and use the guano thus produced for composting and on the beds?

  44. I learn something new from you every time man, it always make sense and your editing is good. good work and many thanks

  45. I have a free and local resourse of bat gauno that does not harm the enviroment. In San Antonio Texas bats live in the cracks under freeway overpasses. One is near whsre I work. The gauno just collects on the cement and will be eventually get washed away by a big rainstorm. I could not stand to see good organic fertilizer go to waste. Late on sunday night so as not to be hit by traffic I got about 30 pounds of gauno. After riding with it in the cab of my truck I must say I prefer coffe grounds! It has a bad smell. I was expecting fast amazing results from it but I was disappointed. It seems to be a slow release fertilizer which is good but from what I read I was expecting a lot more. Urine gets better results than the bat gauno. I am crazy enough to get some more next year with a dust mask and gloves. Bats are small creatures so it may be a year before they make enough guano to make it worth while. Next tume I will keep it in a closed container in the back of my truck. It is made up of dead bugs and will just blow away easily.

  46. Thank you very much for all the precious information on the dangers of bat guano and all the simple/cheaper/more sutainanble alternatives available. I was so close to buying bat guano for my garden… but I'm glad I've found your objective explanations. Many thanks!

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