Why I Don’t Make Laundry Detergent
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Homemade Laundry Detergent. It’s one of those things that almost every crunchy mama makes, right?
Well, not this one.
You know by now that I get a real kick out of MYO (Make Your Own) projects, right?
My husband says I get this little mischievous smile on my face when I figure out a way to make something that we’ve been buying (or not buying because it is just way too expensive :-)), or even when I just think I’ll be able to do so.
I really feel like I am beating the system or something.
Kind of like winning a mini lottery!
Making your own products can be a big help when you are trying to reduce toxins in your life.
Today I am going to tell you one thing that I do not make – and that is homemade laundry detergent.
Here’s why.
Years ago (too many. I’d really rather not think about it :-)) when we lived in the Chicago area, we were living on very little money (ummm..like $13,000 per year). Let’s just say that $13,000 a year doesn’t go very far in Chicago :-)!
My oldest was born and I was forced to leave my job.
Well, really I chose to. My boss reneged on a work-at-home offer and so I quit, not wanting to leave my son with anyone else.
So saving money was a really big deal to me. Really big.
I was buying the loss leaders at the grocery store (we got a lot of funny looks and stares with our grocery cart full of 10 cent oranges or 10 cent yogurts :-)), buying nothing new, and we even lived with my inlaws for 2 years.
Anyway, I had a friend who made her own homemade laundry detergent and for some reason, it really mystified me.
I have no idea why, but there are sometimes projects that stump me for awhile.
I feel like I just can’t get myself to do them for some reason.
Other things like that have been :
– making bread (I ended up with the most amazing whole wheat bread recipe – in our pre-gluten free days)
– making candy (I finally ended up learning how to make lollipops in our pre-sugar-free days)
– making lip balm or deodorant (this is coming soon!)
Laundry detergent was one of them. I would just buy an allergy-free brand at a local store and make it last as best I could.
Well, fast forward about 8 years to our home in Michigan.
I finally got up the gumption to make my own homemade laundry detergent.
I bought myself some Pure Kirk’s Castille Soap (because those recipes featuring Fels Naptha just wouldn’t cut it for this all natural gal. That soap has colors and chemicals and a pretty intense artificial fragrance that really throws me for a loop. Ick.
I grated that soap (I think my grater is permanently soap flavored now), heated it all up in my now soap-flavored calphalon pot (:-().
And used it.
And hubby wasn’t happy.
Maybe it was the lack of fragrance, but he really wasn’t happy with what was going on with his t-shirts.
And I didn’t like making the soap. I got pretty depressed when I saw the bucket was almost empty.
So I tried something new that I am going to introduce to you today – soap nuts!!
What? Nuts that make soap?
Yes. Really. And they work (i.e. no more complaints from hubby). Actually, it’s the hulls that make the soap. Pretty neat eh?
And it’s more than just interesting, it’s good for your wallet.
First, let’s talk about what soap nuts are and how to use soap nuts.
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What are Soap Nuts?
From Naturoli’s website:
soap nuts are the dried shells (or husks) from the soapberry (or soap berry nut). These berries are the fruit from a quite unique tree species. These shells contain a substance called saponin that produces a soaping effect. Saponin is a 100% natural alternative to chemical laundry detergent and cleansers. It can replace many chemical detergents such as those containing sodium laureth sulphate (SLS) that are becoming well known by consumers for being a skin irritant and health hazard.
NOTE: Soap nuts are not nuts – they are fruit. So even if you have an allergy to nuts, soap nuts should be just fine for you :).
Why I Love Soap Nuts
1. They are all natural – no chemicals going on my clothes, on my family’s skin, or into our environment.
2. They are very reasonable. Just pennies per load, especially if you buy the larger bulk sizes.
3. They are super easy to use! And my pots and graters don’t end up tasting like soap!
4. The resulting used-up soap nuts are compostable :-)!
5. Soap nuts leave no smell. I mean, I like nice smelling things, but this way, all you get is clean.
How to Use Soap Nuts
Yes, it’s pretty weird using nuts in your laundry. But they are really easy to use and no, you won’t end up with nut butter in your laundry :)!
1. Put 4-5 soap nuts in a small muslin bag (you buy some of these with your soap nuts).
2. Put a large clip on the bag (this is my handy dandy idea – keeps that soap nuts bag closed tight and keeps it from getting lost in the wash.) I LOVE the large Twixit Clips for this purpose. See below for more info on these great clips!
3. Toss in the washing machine before your clothes go in.
4. Remove from laundry after washing (Naturoli tells me it’s really OK to dry them if you miss this step!)
5. Re-use 3-5 times. Well, truth is I use mine about 6. Cheapskate frugal mama! Told you I like to save money.
6. The above directions are for a warm or hot water wash. If you are going to wash in cold water, soak the soapnuts in a cup of hot water (from the tap is OK – thanks for the tip, Katie of Kitchen Stewardship…Silly me – I’ve been heating water in a pan. But then, especially in the winter it can take awhile for our water to heat up) for about 3-8 minutes prior to use to activate the saponin.
Below is a handy dandy photo of my tiny bag of soap nuts secured with the Handy Twixit Clip and my “heavy duty” plastic container that I use:
More Tips on How to Use Soap Nuts:
1. The biggest tip in my mind is using the Twixit Clip on the bag. Otherwise, I can only imagine how many lost soap nuts bags I’d still be looking for (they’re not very big!) You can use the Twixit Clips for so many other things around the house that it’s great to buy the whole set even if you’re only using one for your Soap Nuts bag. You can see more ways I use them in my posts on How to Store Nuts and Seeds, The Easiest Way to Freeze and Store Berries, and Easiest Sun-Dried Tomatoes. No more pesky twist ties!!
2. I use about 6 soap nuts because I have a front loader and it washes a bigger load.
3. Use a heavy duty container for pre-soaking your soap nuts if you are using cold water for washing. I once decimated a plastic container since it couldn’t stand up to the hot water :-(.
4. After loading the soap nuts into the washing machine, I set the plastic container on top of the washer. Then when the load is done I just find the little bag (with the help of that big clip) and drop it in the container, all ready for the next wash.
5. When it’s time to pre-soak the nuts, I just fill up the container with water, drop it in a saucepan, heat it up and pour it back into the container. Wait a few minutes and run it down to the laundry machine.
6. You can tell the soap nuts are done when they look grayish and are falling apart. Sometimes this frugal mom tries to get just one more load out of them though :-)!
7. Thanks to a reader asking….soap nuts can be used in HE machines.
Why I Use Naturoli’s Soap Nuts
There are a bunch of soap nuts companies out there. I spent a bunch of time researching them (what else is new???) and found that though other brands are cheaper, they may not be real soap nuts. They may not clean as well and they are sometimes not deseeded, meaning that they weigh more.
That means you are paying for the seeds as well which do not do the cleaning. For me, I chose to purchase these since they appeared to be of great value and I have been pleased with them.
Another Homemade Laundry Detergent Alternative
If you are giving up on making your own homemade laundry detergent (like me) and you would like another option besides soap nuts, then here are some other options.
We are using Ava Anderson’s Laundry Pods and are very pleased with them. They are super convenient (just toss one in the back of your front loader) and do a great job.
Update 1/16: I left Ava Anderson due to many labeling issues and wrong / missing ingredients in products. I’ve been on the hunt for a new laundry product and I LOVE this laundry ball!
Super easy to use and it lasts for 365 washes!
Other DIY Household Products
So….I don’t make homemade laundry detergent, but I do make…….
Homemade Foaming Soap
Amazing No Streak Glass Cleaner
Simple Natural Dishwasher Rinse Aid
Plastic Wrap Substitute (well, not really :))
Update on Soap Nuts–aka Can You Have a Soap Nut Allergy?
So, I feel kind of funny adding this BUT–years after writing this post, 2 of us in the family had reactions to soap nuts.
Online it seems that a soap nut allergy is really rare and even some soap nut companies seem to say that it’s not possible, but we definitely had reactions. It might have been something on the soap nuts, but I could never figure out what that was, so we just chose to avoid them after that.
So I went on a hunt for a good natural homemade laundry detergent formula again and found it. I also also developed this DIY Baby Laundry Detergent that’s great for sensitive skin needs too.
Whatever you prefer–Homemade Detergent or Soap Nuts or store-bought, please just do your best to avoid the toxins!
Have you ever used Soap Nuts?
i just use liquid castile soap. by itself.
Interesting. Do you like the results? I have heard it doesn’t clean very well.
ugh, my last comment didn’t go to the right place, it was supposed to be a reply to this. but then it was too long so i had to break it up. anyway, this is the rest of it, lol…
i am very happy with castile soap. we use one we buy by the gallon on amazon that’s made via pedal power in Oregon, forgot the brand, but it’ll be obvious, lol. it seems expensive, but we dilute the gallon, pour half into the old gallon container from the last purchase, then fill both with water, then this is our hand soap, dish soap (not for the dishwasher, i have no eco-friendly options for this—not sure the “if you care” brand is really all that great, but that’s what we use for that) and our laundry soap. we pour into a pretty glass dispenser jar (with the liquor dispensing tops they use at bars) and that’s the laundry “detergent”. the gallons hang out under the sink for refilling dispenser containers we use elsewhere, easy system. just rinse the liquor dispenser lid thingy at each refill—if it’s soapy it doesn’t stay put very well.
to give you an idea, we last bought a gallon in November, and we’re probably ready to buy another one pretty soon, maybe next month… so a gallon lasts us about 6 months now, but i’m pregnant and once the baby is born and we’re washing diapers, i know that’s going to change to probably like 3 months, lol…
So you are diluting and then only using 1/8 cup in the laundry?
we eyeball it, but i am probably using less than 1/8 cup (of actual castile soap) per normal load and a bit more when washing family cloth and kitchen items.
Nice advert for Naturoli Soap nuts. How much did you get paid?
Hi Joe. Thanks for the compliment. It’s not an advertisement or Naturoli. I meant what I wrote. I stopped using DIY Laundry Soap for the reasons I wrote and I really like soap nuts and there are a lot of inferior ones on the market. If you want to buy another brand, go ahead and do it. Through Naturoli I think I made about $30 in the past 6-12 months. Jealous :)? In fact, I’m going to change the links to Amazon asap b/c that doesn’t make any sense.
Hey, at least you’re being honest. To be fair, if you can make a little bit of scratch on the internet, every little bit helps I certainly would do it too, if I could (my talents lie elsewhere). Just be truthful about why you’re writing what you do; if you can’t get the recipe down for homemade laundry, and this is working for you, that’s great.
Also thanks for not deleting my post 🙂
You are welcome. I am being honest. I spent tons and tons of time on my blog (and $60 a year in affiliate payments isn’t enough to make it worth it) and try to update things things as quickly as I can to keep everything reflecting what I do and how companies have changed, but things change very quickly and I can’t keep on top of it all. I’m trying some new DIY recipes hopefully this week to give it another go.
Hello, What size muslin bags do you use??
For washing the small ones are the way to go. Is that what you meant?
I’m using soap nuts for the first time today! What a GREAT page! Thank you!
Thank YOU! Hope they work well for you!
Hmmm … I’m seriously considering giving this a try! Anyone have any opinions on the outcome of washing gym clothes with these nuts?
How is it for removing stains and odors?
Love your website Adrienne! 🙂
Just an fyi….I went to the SmartKlean laundry ball official website and it says on there that buyer beware….these are not sold on Amazon/Ebay by the company and the ones you see on there could be fakes. They may just be trying to get you to buy directly from the company….I don’t know…but thought I would mention it in case the ones on Amazon/Ebay don’t work as well.
This is the link to the official site page that says this. Now I am in Canada so that might make a difference as well.
Thank you for all you do / post…..VERY helpful info!
Hello Paula – First of all, so so sorry for the delay in responding. A lot of comments came in that were spammy, etc., and some that were not got buried. I keep coming and trying to weed through them but this has been way too long!
Thanks oh so much for your kind words (maybe you aren’t so keen on my site now that I took so long to get back to you, LOL!) and I really wonder about the laundry ball now. Have you been using it?
I’ve switched to this and now have another recipe to share….I’m just behind still!
Hope you are well and again, so sorry!
https://en.m.wikipedia.org/wiki/Laundry_ball
According to everything I found online, laundry balls are a hoax. Many studies show that they do the same thing as just washing with water and nothing else.
Interesting. I did notice that our laundry didn’t seem that clean so I’m on the hunt for another detergent now. What do you use? I have friends / acquaintances online who like them so not sure what to make of it?
Soap nuts, thats it??? Sound just too easy. I too am always looking for ways to save, now that Im not working. Thanks for the info
But is this a sustainable way of doing laundry? Where do these fruits grow? Will they be endangered of being wiped out? Where is is native to? You may have found a solution that leads to bigger problems.
Hi Abby. According to the company that I started with, they are sustainable. I am trying out the laundry ball in the post and am loving that so you could try that if you like.
They are generally from the Himalayas (that is where the brand i use are from) and they are sustainable 🙂
https://butterbeliever.com/homemade-laundry-detergent-soap-diy/
Yes, I read that but not sure it’s accurate information.
Hi Adrienne! I am new to your blog, and am in love. I’ve read, and spent way too much time here already! 🙂 I was wondering though, any update on what you use? How was the “Smartklean Laundry Ball”? I was also wondering, what were the issues that presented with your, and your youngest’s allergies? Contemplating whether to try the soap nuts or not!
Thanks for all you do!!
Hi there!
So nice to get such a lovely message – thanks! No update at present. I actually still have some supposedly natural stuff left and will do the ball after that. Well, I can try to do it perhaps. I just was in ER last night all night so I’m not that mobile right now but maybe I can take a run at it for you. I wouldn’t be worried about the soap nuts and I have some I could sell you at a discount if you’d like to try them. We read it’s extremely rare to have an allergy and since then my son has used soap nut shampoo w/ no issues. I suspect it was something w/ the batch. But please do what you like and I’m happy to fill you in on the ball later — maybe my family can get the ball tried out while I’m having this mess :(.
Are soap nuts suitable for cloth diapering?
Yes, they are.
I was introduced to a detergent called SA8. THE..BEST..DETERGENT I have ever used!
Hi there. I just looked up that product – did you see that it has artificial fragrance in it (at least that appears to be the case)? Thanks!
My wife and I use:
1 Bar of Zote
1 Box of Borax
1 Box of Washing Soda
I am very allergic to the dyes and fragrances and this is the only recipe that we have found that does not cause me to break out into hives. It costs us total wise of $15 and we save over $300 per year in laundray detergent.
Hi there. Interesting – did you notice that Zote has artificial fragrance and dyes as well? And it doesn’t bother you?
thats only if you get the pink bars. they have white bars as well without the fragrance and dyes…
I saw Zote white online and it lists fragrance on the label – do you have a different source?
also, borax is a bit of a harsh chemical, i’m really not sure why so many people have latched into it as a supposedly “natural” alternative to just plain soap (like pure castile soap, which is what i use, diluted 1:1 w/ water). i’m also not sure why people seem to think plain old soap won’t do for washing clothes, like there’s something special going on in a washing machine (there’s not, it’s just sloshing clothes in soapy water for a while, so stuff that’s not water-soluble gets dissolved along with the rest (the majority of it) that is water soluble. then it rinses. castile soap requires zero steps, unless you pre-dilute it like me, but i just do that because i use it also as handsoap & dish soap, so i dilute the whole gallon (into two gallons) at the outset. then you can avoid any chemicals, and none of the effort of grating that soap!
I have a post on my site about borax maybe being an issue (it was written by another writer) but I have seen quite the opposite in a number of reputable places, so it’s confusing. As I mentioned above, I have read that castile isn’t a good cleaner but I’m not certain about that.
Are they safe to use in a HE washer?
Yes, they are!
but… Most saponins, which readily dissolve in water, are poisonous to fish. So, if everyone uses this, and the water goes to the river and oceans… this can be terrible, too. (too, because i am trying to find alternatives to laundry soap in behalf of the environment)…
Oh interesting. Hmmmmm…I haven’t done any research on this. Actually I am having some issues w/ the soap nuts. Can you share the data on this and have you found alternatives?
castile soap is harmless, however. when fat mixes with a strong base (like in ashes), there is formation of suds. this process happens in small amounts already in nature. the problem with what most people are putting down their drains is that there are all kinds of chemical detergents and especially strong sudses (even just regular dish soap is crazy, every the natural kinds, compare to castile soap, which is way less sudsy). the many chemicals in detergents have not been tested (most of them) but near effluent sources we see marine life exhibiting all the signs of endocrine disruptor exposure (check out the book Our Stolen Future) and many chemicals are what’s known as persistent (they don’t break down, they build up in their systems). things like castile soap and soap nuts are not persistent, and they’re not particularly strong sudses, so they’re definitely way better, and they’re also easily cleaned out of sewage before release into the ocean, unlike the many other things going down our drains. that said, when you wash clothes with plain water, they usually seem clean. most of what we’re washing out of clothes is salt and sweat and dirt particles, and that just takes tumbling to dissolve & dislodge. so we only need a tiny bit of suds in our laundry to do the job.
I would think that some natural kinds of dish detergent are better than others. We use a very clean one. I am very concerned about the endocrine issues on wildlife.
and note, we don’t use toilet paper, we use family cloth, and we use snot rags instead of kleenex, and cotton towels instead of paper towels, and i use about 1/8 cup (or a little more, i am just eyeballing it) of castile soap for a full load of any subset of these items (though i don’t wash kitchen items together with skin-contact items, that seems gross to me). i use a sanitize setting on my machine to wash these items and dry them extra hot (ensuring no bacteria survive) and everything is super clean and odorless and rarely stained. i think we have a dirt phobia in this culture that makes us use a firehose where a little squirt would do the trick for just about every task. like, i clean my stove, in its entirety, with water & elbow grease. any oil gets absorbed into the rag. we don’t even bother with stinky white vinegar unless it’s to dissolve toilet or hard water stains. and yet most people will reach for the harshest chemical possible to MAKE SURE it’s clean, not realizing water does 99% of the jobs, and a little bit of baking soda or a scrubby pad will get the rest. if everyone would calm down on everything, and they were using castile soap and soap nuts in their wash, our marine life would be in excellent shape.
So where do you store your family cloth after it’s used? I am reading typically it’s recommended to use 1/4 – 1/3 cup castile in a washing machine which would make this method very expensive. Maybe 50 cents a load?
we put the used family cloth in a metal basket on the floor, the unused ones are in a smaller wicker basket on the back of the toilet, and there’s one drawer in the bathroom that is just the cloths, so we can easily refill the small wicker basket every few days. the bin on the floor is usually heaping by the time we do the laundry, and everything is dry before another layer goes on to of the previous, so there’s no mold or smell or anything, and i have bionic pregnancy nose! *note: if a cloth does end up with a dingleberry, we always rinse it off in the sink first before putting in the bin. if a whole drawer devoted to cloth seems a lot, the truth is, it still takes up less room than would a 12-pack of toilet paper. and when you start realizing how toxic most bathroom products are, you find there’s very little left in your bathroom anymore, anyway, besides baking soda! ?
So the “dingleberry” tainted cloth doesn’t stink up your bathroom and are you concerned about parasites on hands after washing that?
well, i really hope i don’t have (unhealthy) parasites, though some people are voluntarily self-infecting with helminths we co-evolved with in order to rebalance their immune systems (and researchers are studying said wormies to figure out if they can isolate their beneficial chemical outputs to commercialize them, of course). but even if i did have a parasite, the truth is, you generally share your microbiome with those you live with. which is a more pleasant way of saying there’s very little risk of you being contaminated with some sort of fecally transmitted microorganisms from a cohabitator that you haven’t already been. the fact is, when they measure bacteria on surfaces in homes, they find fecal bacteria from the residents everywhere. gross to think about, but apparently pretty natural. all that said, i don’t actually TOUCH the dingleberry! i do what i can to avoid that! and i always wash my hands after the restroom. in many countries, they pour water over their bums and rub their bums clean with one hand, then wash. i think americans are too squeamish about all this stuff. 😉
Hi there–can you tell me how you are washing cloths that have stool on them without touching it? I have heard that parasites can live for two weeks under fingernails so that’s one of my concerns. Thanks!
the water just kind of knocks it off (and rinses down the sink drain), and if it doesn’t dislodge, you fold the cloth a bit to get it free with the cloth, not your hand, your hand is always touching a clean part of the cloth (the back side).
but i’m not sure what you’re worried about… if you have a parasite in your poo, that means you already have the parasite. i think the objective would be, get rid of the parasite if it’s problematic, don’t live your life in fear of carrying it around under your fingernails. if you’re that worried about parasites (and no judgment here, i know we all have our things), honestly, it’s everyone else you should worry about. there’s a lot of evidence that people regularly get their own fecal matter on their hands when wiping with toilet paper. there’s nothing to fear in your own home, because you guys will share all gut bugs already. but who knows how careful other people are being! people from India and many people from countries that use bidets (like my dad) are likely to think toilet paper is gross and just smears poo on the bum, and opt for the pour-water-on method with a small cup or pitcher, while rubbing any trace of poo away with their bare hands, then of course washing hands after! i actually use this method if it’s, ahem, a messy situation. and i often get the cloth a bit wet otherwise. i don’t like to have any trace of fecal matter on the outside of my body, not because i’m worried about parasites, but because of smell. anyway, once you’re used to being this clean, it’s hard to go back, and then everyone else, using toilet paper and smearing, they suddenly seem like the gross ones. but i believe my hands are perfectly clean after i wash them. i also see a functional medicine practitioner, so i’ll know if i happen to contract a parasite. it happens to people, yes, but it’s not nearly as common as some folks would have you believe.
I’m concerned after working with health practitioners and seeing the devastation that parasites can cause. And if you have family cloth and you have little ones, mama or dad are doing the washing. And if you are trying to kill the parasites but you have them under your fingernails then you have to be really careful not to infect other people with them.
I’m not living in fear–just trying to figure out a good solution. Thanks! We did cloth diapering and I do not like buying paper anything, so I’m in your court on that totally!
i use about ¼ cup but that’s after diluting, so that’s only about ? cup of castile soap per load. i use less with clothing and more with family cloth & kitchen loads, and just eyeball it most of the time.
that last comment should have said “so that’s only about 1/8 cup of castile soap per load”
So about 25 cents per load then, correct?
Anyone see how there is soap berry liquid? Could you use this the same way as soap berries or maybe include washing soda/borax with it??
I guess it depends on the soap berry liquid. Not sure what you are looking at so I don’t know.
So i am curious, When looking at the attached link to purchase some nuts, it looks like they come in 3 pound quantities. Having never purchased soap nuts, and not knowing the estimate weight per nut, about how many nuts, or loads can you do with 3 pounds??
A lot!! I used 6 nuts per load. You can typically get 4- 6 loads from each set of soap nuts and there are about 6 nuts in 1 ounce. Hope that helps!
this post just had me search for something i recall that also did the same thing.
https://www.aliexpress.com/item/Natural-tea-seed-powder-tea-tree-powder-cake-shampoo-bowl-fruit/1639771106.html
before shampoos, chinese used to use this to wash their hair. I wonder if it can be used to launder clothes?
I have no idea. Interesting. I would think it’s a different process as the powder picks up oil but with clothing it’s typically not oil we are trying to remove.
From what i recall, they also had to boil it in order to have the saponis seep out and have it work. From some of the pictures from some of the other sellers on that site, it looks like grind up soap nuts.
Oh that might make sense. I saw that ground up soap nuts are in some Indian shampoos too.
First, I must admit that I am super skeptical of the granola mommy movement. I think that sometimes, we moms just need to be validated for our giving to our families. Don’t misunderstand my here, I do like granola (super sugary and super yummy), but it seems that this cool, natural, make your own laundry soap living has just been another fad. I have made my own laundry soap, and wound up with slimy lumps of bar soap. The kicker is that it really didn’t save my family money. What I want to know is what the heck is the most econimic way to get my family’s clothes clean.
It is hard. I am considering going back to a DIY recipe but I don’t have time now. Hopefully soon!
Thanks for responding Adrienne. I came to this post because I heard that many modern laundry soaps actually work better in lower temps- therefore saving money. I was wondering if the homemade borax types were in the mix or not, but I don’t see the use in spending the same amount of $, but 10x the amount of work just to claim that what you’re doing is granola righteous
lol!
I don’t know the answer to that question. I like avoiding toxins and synthetics whenever possible but I’m learning more about the downfalls of doing so – especially as I see skincare and cosmetic companies lying about their ingredients and/or them having mold and bacteria contamination issues. Thanks for reading.
i don’t have time to make my own laundry soap nor do i have the desire to fuss around with soap nuts. i buy castile soap by the gallon and use a very small qty of it per wash. another option, if you’re not into castile soap but just want to save money, is use a TINY fraction of the amount of (free & clear) detergent called for on the bottle. like if they say use 1/8 cup, use 2 teaspoons. or buy generic dish soap (which is crazy strong) and use just a few drops per load. it really takes VERY little soap to dissolve the very tiny amount of oils that are on your clothes. most of it comes out with just water. in fact, you could skip soap altogether and you will rarely notice a difference. seriously. anything left gets tumbled loose from the fibers in the dryer, too. traditional soaps and the quantities called for are such overkill.
Just so you know, soap nuts are really no fuss. Put in the washing machine and that’s about it. I don’t think that skipping soap works. I was using a laundry ball and am not sure it worked very well at all.
Today’s definition of Castile soap means any soap make solely of plant oils. Traditionally, Castile soap originating from Castile, Spain, was made only of olive oil. Seasoned soapers will argue only 100% olive oil can be called Castile. That said, if you run a 100% olive oil soap through a lye calculator it’s cleansing property will be 0. A nice mild and conditioning soap, but not suitable for household/laundry cleaning.
i use castile soap (in very minute quantities) for washing my laundry, and this includes family cloth (which we use in lieu of toilet paper), snot rags, and cotton towels in place of paper towels in the kitchen. everything gets perfectly clean.