Sapindus is a genus of about five to twelve species of shrubs and small trees in the Sapindaceae, native to warm temperate to tropical regions in both the Eastern and Western Hemispheres. The genus includes both deciduous and evergreen species. The leaves are alternate, 15-40 cm long, pinnate, with 14-30 leaflets, the terminal leaflet often absent. The flowers form in large panicles, each flower small, creamy white. The fruit, called a soap nut, is a small leathery-skinned drupe 1-2 cm diameter, yellow ripening blackish, containing one to three seeds.
The number of species is disputed between different authors, particularly in North America where between one and three species are accepted:
Sapindus delavayi. China, India.
Sapindus drummondii (syn. S. saponaria var. drummondii) Western Soapberry. Southern United States, Mexico.
Sapindus emarginatus. Southern Asia.
Sapindus marginatus Florida Soapberry. Florida to South Carolina; included in S. saponaria by some authors.
Sapindus mukorossi. India Chinese Soapberry. Southern China west to the Himalayas.
Sapindus oahuensis Hawaii Soapberry or Lonomea. Hawaii (endemic).
Sapindus rarak. Southeast Asia.
Sapindus saponaria Wingleaf Soapberry. Florida Keys, Caribbean, Central America.
Sapindus tomentosus. China.
Sapindus trifoliatus South India Soapnut or Three-leaf Soapberry. Southern India, Pakistan.
Across the jungles of India and Indonesia, a surprisingly practical tree called sapindus mukorrosi grows a small fruit surrounded by a firm outer shell, much like a lychee or rambutan. This tree, also called the Chinese Soapberry Tree, is unique in the fact that it synthesizes its own natural soap-like saponins that coat the shell of the fruit. When the fruits ripen and fall from the tree, local families harvest the windfall, and then remove the inner fruit from the outer shell. The shell is then dried in the sun, using absolutely no chemical processing or manufacturing processes. In fact, the whole process uses no fossil fuels either, except in the transportation of the product to the western world (which is efficiently accomplished by ship).
It is this outer shell, rich in natural saponins which act as water surfactants, that the native families in India have used for centuries to wash their own clothes. They toss two or three shells into a small burlap bag and work it in with their laundry (which is usually washed by hand, by the way). The soap nuts, as they’re now called (even though they have no relation to actual nuts), absorb water and release their saponins which circulate as a natural surfactant in the wash water, reducing the surface tension of the water and freeing dirt, grime and oils from the clothing.
When the clothes are rinsed, the soap nut saponins are washed downstream where they remain harmless to the environment. No synthetic chemicals, no fragrance chemicals, no foaming agents or other toxins. Just pure, natural soap nut saponins grown by a tree and engineered by nature.
Even though these soap nuts have been used for hundreds of years in India and Indonesia, they’re barely known in the western world where brand-name chemical detergents are heavily marketed to consumers through advertising, coupons and in-store displays. Packed in eye-catching boxes and scented with artificial fragrance chemicals, these synthetic detergents are literally scooped up by tens of millions of consumers who have no idea they’re bathing their clothes in cancer-causing chemicals while destroying the environment by flushing dangerous chemicals downstream.
The laundry room is one of the most toxic rooms in the home of a typical consumer. Commercial laundry detergents, fabric softeners and dryer sheets contain alarmingly high levels of toxic chemicals well known to cause cancer, liver disorders, neurological disturbances and hormone disruption. Many people wash their clothes in these dangerous chemicals and then wear them around all day, allowing the chemicals in the clothes to penetrate their skin and enter their bloodstream where they cause serious harm. Even worse, all those toxic chemicals get flushed downstream where they contribute to the mass killing of fish and ocean ecosystems, including all the various lifeforms that depend on the fish.
Until now, there have been few options for eco-conscious consumers. While an increasing number of eco-friendly manufactured laundry products now exist in the marketplace (such as Seventh Generation and Biokleen brands), no natural laundry product had appeared in the western world that is 100% manufactured directly by nature.
Three or so soap nuts per load of hot or warm water wash is the recommended quantity. On their own soap nuts have a mild, fresh, vinegary smell. Yet they will not fragrance the laundry. For added fragrance, add a few drops of an essential oil on the cotton sack. There is no need to remove the soap nuts from the rinse cycle. The little bit of saponin left in the rinse adds softness and body to the laundry. If the laundry feels stiff after washing, however, too many soap nuts were used and excess saponin was in the rinse water. The stiffness will go away after the next washing. Soap nuts can be used for one load with hot water and up to four loads with warm water. If the soap nuts no longer feel squeaky clean or sudsy when rubbed, the saponin is used up. When the shells are ready to retire, add them to the compost. Soap nuts are safe for washing silk, woolens and other delicate fabrics. Furthermore, they are antimicrobial, beneficial for septic systems and greywater, and can be used in the remediation of contaminated soil.
Beyond the laundry room, soap nuts, especially Sapindus mukorossi, are used medically as an expectorant, emetic, contraceptive, and for treatment of lice, excessive salivation, epilepsy, chlorosis, and migraines. Studies show that saponin from soap nuts inhibits tumor cell growth. Meanwhile, they are also included on the list of herbs and minerals in Ayurveda. They are used in Ayurvedic medicine as a treatment for eczema, psoriasis, and for removing freckles.
Soap nuts may be used for various cleaning tasks as well, including removal of tarnish from silver and other precious metals. The price of using these soap nuts is quite comparable to, if not more reasonable than, other eco-friendly laundry products. Granted, it’s not as cheap as dumping foaming chemicals into your laundry. Protecting the environment and well being of family is hopefully more important than saving a quarter here and there. By each of us choosing wisely, it is possible to end the cycle of monetary support for manipulative consumer product companies that poison the world with their harmful chemicals.