Wildflower, rose-pink flowers. Rhizomes contain saponin, can be used to produce soaps.
Hardy to about -20°c. A very ornamental plant, soapwort is often grown in the herb garden and is sometimes cultivated for the soap that can be obtained from the roots.
Soapwort should not be grown next to a pond with amphibians or fish in it since if the plant trails into the water it can cause poisoning. The flowers are slightly scented with a sweet aroma that has an undertone of clove. Hybridizes with other members of this genus.
A good moth plant.
A soap can be obtained by boiling the whole plant (but especially the root) in water. It is a gentle effective cleaner, used especially on delicate fabrics that can be harmed by modern synthetic soaps (it has been used to clean the Bayeaux tapestry). It effects a lustre in the fabric. The best soap is obtained by infusing the plant in warm water. The roots can be dried and stored for later use. The plant is sometimes recommended as a hair shampoo, though it can cause eye irritations.
The plant spreads vigorously and can be used as a ground cover when planted about 1 metre apart each way.Best if given a short cold stratification. Sow autumn or late winter in a cold frame. The seed usually germinates within 4 weeks. Prick out the seedlings into individual pots when they are large enough to handle and plant them out in early summer.
Succeeds in any moderately fertile well-drained soil in sun or semi-shade. Prefers a neutral to alkaline soil.