4 Plants You Can Use Instead of Soap – This Ancient Cleaning Method Is Making a Comeback in Eco-Friendly Homes

Are you looking for a natural replacement for soap? Certain plants contain the compound saponin that lathers when mixed with water and are effective cleansers.

These plants historically were used as a soap to wash hands and clothes. You may already be using some of these plants in your garden right now to attract pollinators, but they can serve double duty as soap as well.

Many plants that can be used as soap are native to the U.S. and easy to find. If you want to try making natural soap at home out of plants from your garden, here are a few of the best ones to try. Plus, I'll show you how to extract the saponin to make your own eco-friendly soap the way people have for centuries.

How to Make Soap From Plants

You can make soap out of plants that contain saponins by pruning off the part of the plant that contains the saponins and mixing it with water. Typically the leaves and roots are highest in saponins. It won’t get really soapy, but it makes a slight lather.

You can boil water and the required plant parts to make a liquid soap. Simply let it cool after straining the mixture, then store it in a clean bottle or other container, like these glass pump soap dispensers from Amazon.

To retain freshness, add 2 teaspoons of apple cider vinegar. To give it a scent, add a few drops of essential oil to the mix. Homemade soap is not as thick as a commercial liquid soap, but works just as well.

Best Plants to Use as Soap

Here are plants worth growing that contain saponin and are suitable soap replacements:

1. Soapwort

Soapwort (Saponaria officinalis), also called bouncing bet, originated in Europe but has naturalized in the U.S. You may see it along roadsides or growing near water. In the garden it makes a pretty perennial wildflower with clusters of pink, rose, or white flowers.

The sap of the flowering stems, leaves, and rhizomes are high in saponins and this plant produces soap when mixed with water. Grow it in full sun in well-drained soil. It is hardy to USDA growing zones 2 to 8.

Note: The roots and seeds of soapwort are toxic to humans if consumed and can cause nausea, vomiting, and diarrhea.

Buy heirloom soapwort seeds from Etsy for only a couple dollars.

2. Soapweed Yucca

Soapweed yucca (Yucca glauca) is a perennial plant native to the Great Plains and prefers a rocky, dry, well-drained soil in full sun. Its long, linear leaves form a rosette. Hardy in USDA zones 4 to 8, soapweed yucca attracts butterflies and provides cover, food, and nesting for various wildlife species.

The saponins are found in the plant's roots, which cause a toxic reaction to horses and pets. To use yucca plants to make soap or shampoo, crush the roots with water to form a lather.

Shop soapweed yucca seeds on Amazon.

3. Soapberry

The skin of the dried berries from the soapberry tree (Sapindus spp.) can be used to make dish soap, shampoo, hand soap, body wash, and laundry detergent.

Western soapberry (Sapindus drummondii) is hardy in USDA zones 6 to 9, while Florida soapberry (Sapindus saponaria) is only hardy in zones 10 and 11. Florida soapberry prefers full sun and grows 30 to 40 feet tall (9 to 12 m) in most soil types.

This unique evergreen tree produces gold berries that can be used for soap. The seeds inside are poisonous, so grow this tree in an area where children and pets are not allowed.

Plant Western soapberry in part to full sun in most soil types. It reaches 40 to 50 feet tall (12 to 15 m) and is an ideal shade tree with glossy leaflets. Its leaves turn gold in the fall before dropping. The yellowish berries of the Western soapberry are smaller than Florida soapberries, but both are poisonous.

According to the University of Florida, you can make liquid soap using the skin of the dried berries. Use one quart (1 L) of water per 10 soapberries and boil for about 20 minutes.

Allow the mixture to cool completely before straining the liquid. Store it in a clean container with 2 teaspoons (10 mL) of apple cider vinegar, which acts as a natural preservative. To scent the mixture, add a few drops of your favorite essential oil.

You can grow your own soapberry tree with seeds from Walmart or buy prepared soapberries from Amazon that are ready to use as a cleaning agent, if you aren't able to grow this tree in your own yard.

4. Horse Chestnut

The common horse chestnut tree (Aesculus hippocastanum) is a non-native flowering species often used as a street tree. The horse chestnut’s white flowers are showy, long-lasting, and attract hummingbirds and bees. Grow horse chestnut trees in full sun to light shade in well-drained soil in USDA zones 3 to 8.

You can make laundry soap or shampoo by crushing the conkers (aka nuts) and boiling them in water for about 20 to 30 minutes, then straining the mixture into a clean container.

All parts of the horse chestnut tree are highly toxic to humans, horses, and pets, if ingested. Poisonous horse chestnuts are often confused with the edible American chestnuts (Castanea spp.) that are part of the beech family. When in doubt, don't ingest any part of a plant you cannot identify.

Grow a horse chestnut tree with seeds from Amazon.