This old world perennial, with its profusion of blooms and vigorous growth habit, has made a home in gardens everywhere. Along with being grown for their showy flowers, these plants were commonly grown for more practical reasons: as soap. Though it is less in use as a cleaning agent now, it still has a special place in many herb and cottage gardens.
Soapwort is prized for its long-lasting blooms. Available in many shades of pink and white, these little flowers are reminiscent of phlox blossoms and bloom freely for months and months, usually starting in late spring, with some varieties carrying on well into the fall months. The flowers have a lovely sweet fragrance, especially in the cooler evening hours. Low-growing types look good spilling over walls in rock gardens, troughs, and containers. Taller varieties work well mixed with other tough perennials, and are seldom bothered by deer or rabbits because of their bitter taste.
About Soapwort Sap
Soapwort first became popular as an ingredient in a gentle soap solution. All parts of the soapwort plant contain high levels of saponins; these compounds can be used to make a mild detergent that's easily dissolved in water and good for cleaning delicate items like lace or sensitive skin. Saponins are poisonous to fish, so avoid planting near ponds and water gardens.
Soapwort Care Must-Knows
Soapworts are easy plants to grow and can be potentially invasive. They can thrive in rocky, sandy soils but for best results, plant in lean, well-drained soils. If the soil is too rich, the plant can become overly lush and floppy, taking on a messy look. Lean soil also helps reduce unwanted spreading.
Plant soapworts in full sun to encourage more compact growth and maximize blooming. When the show is over, shear the plants back for a tidier look and to minimize reseeding. If you are worried about them becoming invasive, grow soapworts in a container, or look for varieties that are a bit tamer.
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