DIY washing-up liquid with black soap, bicarbonate of soda and washing soda crystals

Supermarket shelves are packed with bright washing-up liquid bottles: Ultra, Power, Sensitive, Citrus. What hardly anyone pays attention to is the label: a blend of chemical surfactants, fragrances and dyes that can end up in waterways, arrives in plastic packaging, and often irritates skin. That is why more and more people are switching to a straightforward home-made mixture - and suddenly they no longer need to buy washing-up liquid at all.

Why conventional washing-up liquid can become a problem

Commercial washing-up liquids are usually designed to do two things: cut through grease powerfully and smell pleasant. To achieve that, several groups of ingredients typically go into the bottle.

• Synthetic surfactants break down grease especially quickly, but do not always fully biodegrade in the environment.
• Fragrances and colourings create a “freshness feeling”, yet are often unnecessary and can increase the likelihood of allergies.
• Preservatives keep the product stable for longer, but add to the burden on waterways and sewage treatment.
• Plastic packaging can only be recycled to a limited extent; much of it ends up in general waste or is incinerated.

On top of that, many people use far more washing-up liquid than they need. A high foam cap in the bowl looks reassuring, but it says little about actual cleaning performance. The result is that unnecessary amounts of chemicals go down the drain - and onto your skin.

Wer auf ein selbst gemachtes Spülmittel setzt, spart Plastik, Geld und reduziert gleichzeitig die Menge an Chemie in der eigenen Küche.

The simple mix with black soap: three ingredients instead of a chemical cocktail

This household alternative relies on three basic ingredients you can pick up in any chemist, and which have been used around the home for decades:

• Black soap (liquid)
• Bicarbonate of soda (baking soda)
• Washing soda crystals

Black soap forms the base and provides the main cleaning power. It is traditionally made from plant oils such as olive oil or linseed oil and comes without problematic additives. It cuts grease without drying out the skin as much as many industrial products.

Bicarbonate of soda is mildly abrasive and helps neutralise odours. Dried-on food tends to lift more easily without scratching non-stick pans or glassware. Washing soda crystals tackle grease head-on: they help saponify fats - in other words, turn them into something water-soluble - a classic technique borrowed from soap-making.

How to mix your own washing-up liquid

For roughly half a litre of home-made washing-up liquid, you only need small amounts of the three components. The version described here is easy to replicate:

1. Put 1 tablespoon of bicarbonate of soda into an empty, clean bottle.
2. Add 1 tablespoon of washing soda crystals.
3. Pour in about 2 centimetres of liquid black soap as the base.
4. Top up with hot tap water, leaving a little space at the top for shaking.
5. Close the bottle tightly and shake vigorously until the crystals have dissolved.

The result is a mild but highly effective cleaner. If you want, you can add a few drops of essential oil - for example lemon or lavender. This is optional, but it can help shift unpleasant smells from plastic food containers or pans.

Version with grated household soap

A more substantial variant also includes a traditional bar soap, such as a block of additive-free household soap. This option produces a thicker, more strongly foaming washing-up liquid:

• 800 ml hot water
• 1 tablespoon black soap
• 1 tablespoon washing soda crystals
• 1 tablespoon bicarbonate of soda
• about 50 g finely grated household soap

Put all the dry ingredients into a bowl with the black soap, add the hot water, and stir well until the soap has mostly dissolved. Leave the mixture overnight. The next day, dilute with a little cold water if needed and decant into a bottle. You end up with a thick, foaming cleaner that you can use much like a conventional washing-up liquid.

How well does the home-remedy mix actually clean?

Many people initially worry that a home-made cleaner will not compete with the aggressive supermarket products. However, experiences after several months of use suggest otherwise: plates, cutlery and glasses come out clean and grease-free, and pots shine without any slippery film being left behind.

One noticeable difference is that the mixture foams far less than familiar branded products. It can feel odd at first, but it does not indicate weaker cleaning. Foam is largely created by certain surfactants and air - not by “more cleanliness”.

Wirklich entscheidend ist, ob Fett und Speisereste verschwinden – nicht, wie hoch der Schaum im Becken steht.

A welcome side effect: in many households, drains seem to clog more slowly. Washing soda helps break down grease in pipework, which can reduce build-up. If you already rinse through with hot water regularly, you can take ongoing pressure off your kitchen waste pipes.

Financial benefits: washing up for a few pence per litre

The ingredients for this home-made washing-up liquid are among the cheapest items in the chemist. A pack of bicarbonate of soda, a box of washing soda crystals and a bottle of black soap will make many litres of cleaner. When you work out the cost per bottle, it comes to just a few pence.

By comparison, branded washing-up liquids can cost several pounds per litre in shops. Add in special offers, fragrance options and “premium” versions that mainly include a marketing mark-up, and the price climbs quickly. Mixing your own lets you sidestep that spiral.

Less plastic, fewer chemicals, fewer irritations

Another change many users only notice over time is that the skin on their hands becomes calmer. Red patches, tightness or itching can ease when the harsh chemistry disappears from everyday washing up. Gloves are still sensible for longer sessions, but plenty of people find they cope far better with this home-remedy mix.

At the same time, plastic use drops. Instead of buying a new bottle every few weeks, you can keep refilling a sturdy dispenser or an old bottle. Buying larger packs of the base ingredients can reduce packaging even further.

Where the home-made washing-up liquid reaches its limits

The mix is not perfect for everything. For heavily baked-on casseroles or burnt pans, you will often need an extra step: soak overnight, possibly sprinkle on a little baking powder or salt, and pour over hot water. After that, the residue usually lifts far more easily.

It is also wise to check care guidance for very sensitive materials such as natural-stone worktops or certain wooden surfaces. Washing soda is alkaline and, in high concentrations, can attack some finishes. In normal dilution in washing-up water this is not an everyday issue, but concentrated solutions should not be left to dry on delicate surfaces.

Practical tips for everyday use with the home-remedy washing-up liquid

• Give the bottle a quick shake before each use so the ingredients redistribute.
• If you have very hard water, add a splash of vinegar to the washing-up bowl now and then to help prevent limescale marks.
• For glasses, a small squirt is often enough - less really is more.
• For very greasy pans, wipe out first with kitchen paper, then wash up. This saves cleaner and is kinder to your drains.
• Once a month, flush the drain with hot water and 1 teaspoon of washing soda to help keep the pipe clear.

What is behind the key ingredients?

Bicarbonate of soda is a versatile household staple: it neutralises odours, reacts mildly alkalinely, and is also useful for cleaning an oven, fridge or trainers. In this washing-up mixture, it helps loosen food residue and reduces unpleasant smells.

Washing soda crystals are different from bicarbonate of soda: they are more strongly alkaline and much more powerful at cutting grease. For that reason, they should be kept away from children and not inhaled. Used at the right dose in washing-up water, however, they are an effective aid against greasy films.

Black soap adds plant-based washing substances to the blend. Unlike many brightly coloured branded products, it comes without optical brighteners or potentially problematic fragrances. Many versions biodegrade more readily and are gentler on the skin.

Once you understand these three building blocks, it becomes clear why so many households stop buying conventional washing-up liquid. The home-remedy mix cleans reliably, costs very little, is better for the environment - and can be mixed up again in just a few minutes when the bottle is empty.

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