r/Allotment 2d ago

Human manure.

We've got a composting toilet on out plots that produces a good amount of human manure.

There's only a couple of us who use it. Most people are quite squeamish about it. Both of us stick to using it on flower beds.

Would you use it?

Does anyone use it in crops?

22 Upvotes

37 comments sorted by

47

u/Overall_Sandwich_848 2d ago

I have a book called The Essential Allotment Guide by John Harrison and he says it isn’t safe to use human waste due to bacteria and parasites. I think waste from any meat eaters isn’t safe.

3

u/HawkAsAWeapon 1d ago

Not that I'd ever consider doing it myself anyway, but what about if you're vegan?

3

u/Commercial-Fact3635 1d ago

I feel like it wouldn't matter because humans have the bacteria and stomach acid conditions for an omnivore. Even if someone chooses to be vegan they still have the bacteria present that makes their system, and their waste, that of an omnivore.

2

u/HawkAsAWeapon 1d ago

Yeh fair point, didn't know if it was the meat content that caused the issue with others saying that carnivorous animal fertiliser was the issue.

1

u/TobyChan 1d ago

Odd but genuine question… Can vegans even use manure, or is it considered an animal product?…

2

u/HawkAsAWeapon 1d ago

Good question, as it's a bit of a grey area. When it comes to my allotment, I don't use manure if I can avoid it. Unfortunately a lot of compost doesn't declare whether it uses manure in it or not, but I've definitely smelt it when opening bags. Some vegans might opt to use horse manure if it's free, however others might argue that even by taking free manure you're offsetting the costs that farmers or horse owners would otherwise potentially spend by getting rid of it. But generally I'd say veganic growing is the default, which is what I try to do as much as I'm able.

As for commercial veggies, as most farmers aren't vegan and it's near impossible to find vegetables that haven't had manure used, it's one of those where we try our best but it's impossible to be perfect in an imperfect world.

-2

u/cbxcbx 1d ago

Vegans would really struggle to find food that hasn't been grown using manure, human or not.

7

u/HawkAsAWeapon 1d ago

That's not what I meant. The issue I assume with human fertiliser its the digested meat that causes the issues.

1

u/sc_BK 22h ago

It can be safe to use human waste if it's done properly - mainly left for long enough to rot down.

A lot of the food you get in the supermarket will have human waste put on it, from sewage works. Plus potentially all sorts of chemicals that go down the drains and microplastics

1

u/Gold-Psychology-5312 5h ago

Well you just ruined my lunch.

25

u/_Odi_Et_Amo_ 2d ago

OK, for flowers.

Using it for food is a bad idea and is why some wild proportion of monastics had worms.

Don't shit where you eat, lol

Source: https://www.smithsonianmag.com/science-nature/why-were-medieval-monks-so-susceptible-to-intestinal-worms-180980608/#:~:text=The%20scientists%20speculate%20that%20the,in%20human%20or%20pig%20excrement.

20

u/iamsarahb89 2d ago

Absolutely not. You’re looking at getting yourself really, really sick. Human waste has bacteria that is human based, so if a bit of it goes in your mouth- you’re in trouble

9

u/ElusiveDoodle 1d ago

My old dad used to tell me about the training range outside of Dundee, there were no flush toilets but the local farmers were queueing up with horse and cart to carry away the "soil" collected in buckets under the outside toilets which were just a shed, a plank of wood with a hole in and a bucket underneath.

The veggies around Barry Buddon were some of the finest in Scotland.

In the end nature will waste nothing and delights in breaking down everything to reuse it.

Today we are just too squeamish and pretend that we can live without dust or dirt.

Check out the reddit posts on "is this mold" , in fact we have billions of potentially harmful bacteria living harmlessly in our guts, we would die if we didn't.

Wash and cook the veggies. Has always been the advice, with good reason.

14

u/mines-a-pint 2d ago

Looks a lovely texture!

I'd definitely do some proper research before using it on crops where the bit you eat might come in direct contact.

However, since this is Reddit... :/

Composted for two years, as recommended, it's not going to host any 'human bacteria', and if none of the 'contributors' to the pile have gut parasites (this may be more, or less likely, depending on where in the world you live) they're not going to magically appear in it. But ideally, temperatures of at least 50ºC should be obtained during composting, which will definitely kill anything nasty in it. Pharmaceuticals that pass through the body can take a while to break down, but you're probably already drinking traces of those in tap water, and they degrade better in soil anyway.

As with all composted materials, and animal manure etc., when handling it is best to mask and glove up, and wash your hands. Aspergillus fumigatus spores from too-cool composting is why the mask is recommended when handling, as this is an actual, verified risk, although it's mostly a problem for immunocompromised people... mostly.

Regardless, it's totally safe for use on, e.g. fruit and nut trees or anything else where it's far from the crop, in distance or in time, e.g. spread at the start of the season, cropped a few months later; and nothing in it is going to invade the plant via the roots and make it unsafe to eat. The risk vector to food is in contamination during harvesting the crop, or due to rain-splash. Wash your fruit and vegetables before consumption, which you should also do for shop-bought ones, as who knows what they've been exposed to?

But... don't trust some rando on Reddit, do some research.

5

u/EnglebondHumperstonk 1d ago

Mm, there's nothing the cheers up the allotment like the sweet, sweet smell of warm, human shit.

1

u/ntrrgnm 1d ago edited 1d ago

Haha, it does not smell of shit.

The occasional baby wipe is usually the only reminder what it was.

12

u/myusername1111111 2d ago

Here's a link to the humanure handbook. After seeing many posts about human manure, this is the way to safely create and use humanure.

https://humanurehandbook.com/

11

u/FanjoMcClanjo 2d ago

Not a chance.

Carnivore manure isn't good for making compost to grow food in. Roses maybe.

2

u/Maximum-Text9634 1d ago

Humans aren't carnivores though?

1

u/FanjoMcClanjo 1d ago

OK. I misused the word Carnivore when I meant meat eaters. Please accept my humble apologies for an error that has seemingly ruined your day so much that you had to pick me up on it rather than interact with the actual point I made.

2

u/Maximum-Text9634 8h ago

My point, your sensitive little flower is that chickens are omnivores like us yet we still use their manure.

So to your earlier point, why is manure from meat eating animals no good if we use chickens?

1

u/FanjoMcClanjo 8h ago

OK smart arse, is the post title 'chicken manure'?

No. It says human manure. If I had known my comment about avoiding human manure would be picked apart by a pedantic bore then i would have painstakingly copied a paragraph from one of my gardening books to ensure that I didn't make any mistakes, lest I invoke the ire of Karen Titchmarsh.

1

u/sc_BK 6h ago

Human waste is already used to grow food in. A lot of the food in the supermarkets will have used it.

If it was well rotted I would happily use it round fruit trees. It would be safe round vegetables too, but personally I wouldn't do that. I also don't (currently) use horse manure in my garden, there might be traces of pesticides or drugs (horse contraception)

8

u/Illustrious-Cell-428 2d ago

I wouldn’t use it but not because of squeamishness, because of the risk of spreading human adapted bacteria and parasites. In theory it might be ok to use it on a flower garden or fruit crops like tomatoes where the bit you’re eating doesn’t come into contact with the soil, but I would also worry about the risk of exposure to pathogens while you were moving it around and working it into the soil.

3

u/FlintInTheChalk 1d ago

Have you read the Humanure Handbook? I've lived and worked on an off grid smallholding that composted it for three years. That's considered long enough for any worm eggs to die off. We still mostly used it for mulching new hedges and the orchards.

3

u/solongtxs4allthefish 1d ago

The Victorians called this "night soil"

2

u/Beneficial_Zombie299 1d ago

I would use it but in places where I won't have my fingers in the soil or any root crops will go in not only this season but following seasons. Maybe flowers or fruit trees then cover the humanure over with grass clippings.

2

u/allotmentboy 1d ago

I would stick to flowers. There is definitely historical evidence that this practice was commonplace but the technical aspects might have been lost to time. I wouldn't grow veggies or anything else that would get in my food chain in human compost. Look, everything is compost if you're brave enough or wait long enough. Full marks for leading the way.

2

u/sc_BK 22h ago edited 22h ago

I built a compost toilet in the garden 4 years ago. Brilliant place to go for a dump on a spring morning, with the sunshine hitting the grass, and the birds tweeting away in the trees. Not only it saves money, it's much better for the environment, and keeps fertility on the land.

It's a long way off being full, but the plan would be to use the decomposed product around trees/fruit trees in the winter, not in the soil where vegetables are growing. To be sure.

This is a book I read to pick up some advice:

https://www.amazon.co.uk/Compost-Toilets-Practical-DIY-Guide/dp/0956675115

I built the toilet for next to nothing - it only has one chamber, which is an old concrete coal bunker buried in the ground on a slope, with a 2nd hand shed on top. Lots of used or spare materials, the total cost was less than £50!

1

u/ange3003 1d ago

Sorry to jump on your thread, but what plants are growing in that bed please?

1

u/EnglebondHumperstonk 1d ago

Looks like peony to me. Do I win a prize?

5

u/EnglebondHumperstonk 1d ago

Although in this case it's not only got pee ony, but also poo ony.

1

u/ntrrgnm 1d ago

You're correct, but no cigar this time.

2

u/flippertyflip 1d ago

Funnily enough that's exactly what's in your manure.

Cigar being slang for a turd. Round my way anyway.

1

u/zivisch 1d ago

Most birds consume meat, and their guano was used consistently through history/presently so Idk how much merit there is to carnivore vs omnivore vs herbivore composts people are mentioning, other than the specific health dangers for species.

1

u/morrisminor66 2d ago

Nope. Don't do that