All You Need To Know About Cleaning With Castile Soap

Here’s your ultimate guide to castile soap for cleaning. Discover what this natural cleaning powerhouse is, explore its many uses, find out where to buy it, and much more.

Castile soap is an incredibly versatile type of soap that has a whole host of uses around the home. In fact, one bottle of soap could replace many cleaning products in your home.

But while you may have heard of this natural cleaning wonder, you might not know how best to use it. Don’t get in a lather – let me talk you through everything you need to know about using this soap for eco-friendly cleaning applications.

From what this wonder soap is, to how to use it, and what not to mix it with – here’s almost everything you could ever need to know.

Everything You Need To Know About Cleaning With Castile Soap

Let’s roll up our sleeves, don our rubber gloves, and find out all there is to know!

What Is Castile Soap?

First up, I always think it’s helpful to know what castile soap is exactly.

Unlike chemical-based products with complicated ingredients, castile soap is simple and natural. It’s a vegetable-based soap made without synthetic additives or animal fats. This makes it non-toxic, biodegradable, and vegan.

Originally from the Castile region of Spain – hence the name – it was traditionally made with olive oil. Whilst olive oil is the traditional base, many castile soaps today are made with coconut oil, and occasionally with castor, hemp, avocado, walnut, or almond oils. These oils are what give the soap its rich lather and effective cleansing properties.

How Does Castile Soap Work?

Wondering how such a simple product is good at cleaning? It’s because the soap acts as a surfactant. What this means is that the soap has the ability to lower the surface tension between water and dirt, grease, or oils.

How does that work? Well, soap molecules have two very different ends, which is what makes them such effective cleaners. One end is hydrophilic, meaning it’s attracted to water. Meanwhile, the other end is hydrophobic and naturally attracts oils and grease.

When castile soap is mixed with water, the hydrophobic tails cling to greasy dirt, while the hydrophilic heads stay connected to the surrounding water. As you rinse or wipe a surface, the water carries those soap molecules away, lifting the trapped dirt and grease with it.

Castile Soap Formats

Castile soap is available in both bar and liquid formats.

Wondering which version to buy? I personally prefer the liquid version for its versatility. However, you can also melt the bars to make liquid soap, which is a great option if you’re aiming to reduce plastic waste.

How To Use Castile Soap Around Your Home

Liquid castile soap is very versatile and can be used in a huge variety of ways – from naturally cleaning your home to your body. You just need a small drop – the soap is only ever used highly diluted – so one bottle can go a long way.

Here are just some of the many uses for it:

• A tiny drop – just two teaspoons – makes this all-purpose DIY cleaning spray. This spray is effective in cleaning every nook and cranny in your home.
• You can also make this stone-safe homemade cleaning wipes solution (pictured above). Again, this recipe just requires two teaspoons of soap.
• Even your makeup brushes can benefit. This makeup brush cleaning solution requires just one teaspoon of soap for naturally clean brushes without the use of any harsh chemicals.

I also use it to make liquid hand wash, floor cleaner, and laundry powder, among many other uses. For these recipes, and lots more uses for castile soap – try Fresh Clean Home – my book on how to make your own natural cleaning products.

Not convinced? Dr. Bronner’s – the main brand when it comes to castile soap – claims their soap is an 18-in-1 product. They say you can use their soaps for washing your face, body, hands, and hair. You can also use their soap for brushing your teeth, shaving or bathing, and for aromatherapy.

But it doesn’t stop there. You can also use their soap for rinsing fruit, washing dishes by hand, doing laundry, mopping floors, all-purpose cleaning, washing windows, and scrubbing toilets. They even say you can use their soap for washing dogs and controlling dust mites, ants, and aphids. Phew. It has A LOT of uses!

Check out all the uses for castile soap here if you remain unconvinced!

What Not To Clean With Castile Soap

Castile soap is really versatile and can be used in most circumstances. The only time I don’t use it is if I am cleaning mirrors or windows. Although Dr. Bronner’s says you can, I find it tends to leave a cloudy film that needs a lot of extra buffing to remove.

I also don’t like to wash dishes with it – again, even though Dr. Bronner’s says you can – as I find it leaves a residue on my glasses.

Does It Disinfect Surfaces?

Now that we’ve established that castile soap is good at cleaning most surfaces, you may well be wondering if it can disinfect surfaces in your home.

The short answer is no. Castile soap is a cleaning agent. It acts as a surfactant. This means that when you wipe a surface with soap and water, it removes dirt and grease, as well as germs and bacteria from surfaces. Like most cleaning agents, these surfactants don’t kill germs – they just allow you to wipe them away.

Antibacterial or disinfectant products, on the other hand, aren’t cleaning products. They don’t clean anything. They kill germs but don’t necessarily remove them. There are also concerns that overuse of antibacterial products can contribute to the rise of bacterial resistance to antibiotics, so it is best only to use these products when necessary.

Soap and water are generally enough to clean most of your home and keep you and your family healthy. Public health bodies recommend that soap and water are effective when washing our hands to prevent spreading germs. The same is true of our homes.

Antibacterial or disinfectant products are useful when you want to clean surfaces where raw meat has been prepared, or for cleaning hard surfaces when someone in your household is unwell.

In this case, soap is best used in tandem with an antibacterial spray to kill any lingering germs. I like using these plastic-free refill anti-bacterial sachets (from Big Green Smile) for no-fuss, zero-waste germ-killing. 

The Things Not To Mix It With

Whilst the soap is great at cleaning, there are a few natural cleaning products you should keep it well away from.

I find that you shouldn’t mix castile soap with acidic natural cleaning products such as vinegar or citric acid.

It won’t cause you any harm if you accidentally mix them. However, if you are looking to clean your home effectively, you don’t want to combine them.

This is because castile soap is alkaline. You may remember from school science lessons, when you mix an acid with an alkaline a chemical reaction occurs. A new substance is made, or you end up with a neutral solution.

In the case of mixing castile soap with vinegar, the reaction neutralises both, reverting the soap back to its original oils.

In simple terms, if you mix castile soap with an acid, you’ll notice the soap curdles. It will also feel very oily. If you use it on your hands or on any surface, you’ll notice that it leaves a white film that is very difficult to remove.

If you want to get fancy, this oily curdled outcome is called unsaponified fat. This means the vinegar has reverted the soap into its raw materials. The soap isn’t much use in its raw material state, so I wouldn’t recommend mixing it with acid.

If you do want to mix soap with vinegar, use washing-up liquid instead. Washing-up liquid is much less delicate and can withstand being paired with vinegar.

Where To Buy Castile Soap

Castile soap is easy to find. Find bottles in most health food stores, or buy online. Check out my guide on where to buy liquid castile soap for a quick run-down on all the best places.

Don’t have time to click? You can buy branded Dr. Bronner’s liquid soap at Big Green Smile in a variety of sizes and scents. These range from 60 ml if you just want to try it out, all the way through to big 3.8 L bottles – it’s the biggest selection I’ve found.

If you would prefer unbranded and unscented soap, then try Etsy’s selection. Here you will find unbranded and unscented soap at a lower price point. If you are using it for making your own cleaning products, then you can add your own scent with essential oils.

For solid soap bars, you may be able to pick these up in health food stores or some larger supermarkets. Online, Big Green Smile has a large selection of solid bars.

More Green Cleaning Resources

Got any more questions that I haven’t answered here? Leave me a comment below and I will try my best to answer it.

And looking for more green cleaning inspiration? Check out my ultimate guide to making your own natural cleaning products. I’ve got tons of recipes and helpful guides to help get you started.