Soapwort in the garden by Ruth Ridley

Saponaria is a traditional wash day herb

Soapwort, Saponaria officinalis, is a ubiquitous herb where I live in the South East. I have never grown this plant for its herbal qualities, and wasn’t even aware of them until recently, although the name is a bit of a clue to its uses!

Pale pink flowers

I first came across soapwort when I lived in a rented house in Peacehaven on the South Coast for 18 months in the 1990’s. It grew profusely outside my front fence, flowering reliably all summer. So I couldn’t resist taking a few cuttings with me when I moved to my current home a few miles along the coast in Seaford. The same plant now graces the same position in front of my fence welcoming visitors – it is a bit rampant but worth it! (I hear it can be a nightmare to get rid of, but I’m a sucker for easy-to-grow plants!).

soapwort gardenAfter moving here, I started getting the train to London from time to time, and started noticing a similar soapwort growing along the tracks at the Sussex end, next to self-sown hedges of buddleja.

A naturalised Sussex herb

Reading Downland in Flower by W.N. Macleod, I realised that soapwort has strong historic ties to the area. It is associated with former areas of industrialisation and textile manufacture. It was once a commercial crop grown close to woollen mills for its saponin content.

Using soapwort as a natural detergent

making soapwort liquid

To use soapwort as a mild detergent suitable for linen, lace and delicate woollens, fill a saucepan with leaves and crushed stems and add enough boiling water to just cover. Simmer for 15 mins, then wring out and sieve. You will notice that a foam forms easily on the surface. This liquid soap, once cooled, can be used to carefully cleanse textiles.soapwort liquid detergent

It is thought that the possible antibiotic effect of saponins may be of use to the plant in protecting it from soil-borne pathogens.

Read more – Information on growing saponaria from the RHS.

[Disclaimer – do test this method thoroughly before using on your most prized fabrics as we can’t be held responsible for any mishaps.]


Written by Ruth Ridley