Common soapwort, or bouncing bet, is a European wildflower whose leaves and roots make a soapy lather when rubbed or boiled in water. Brought over as a garden plant, it escaped and is now naturalized across much of North America, along roadsides, ditches, and stream banks. Its sweet-scented pink or white flowers bloom from midsummer into early fall.
Appearance
- Growth form
- A perennial that grows about 1–3 ft (30–90 cm) tall. Vigorous underground let it form patches and colonies.
- Leaves
- Opposite, oval to lance-shaped leaves up to about 4 in (10 cm) long, with little or no stalk. Three prominent parallel veins run the length of each leaf.
- Flowers
- Flowers about 1 in (2.5 cm) across cluster at the stem tops. Each has five slightly notched petals that spread out and then curl back as they age, above a long, slender tubular . Flowers open in the evening, last about three days, and smell strongest at night.
- Flowering time
- July through September in the Upper Midwest (for example, Minnesota).
- Fruit
- A capsule that stays enclosed in the old calyx.
Look-alikes
Garden phloxPhlox paniculata
Check the leaves: bouncing bet has three prominent parallel veins on each leaf, which phlox lacks.
Why they get mixed upBoth carry summer clusters of pink, five-petaled flowers at the top of the stem.
Where it lives
- Typical habitats
- Roadsides
- Ditches
- Fields
- Stream banks
- Woodland edges
- Range
- Native to Europe and east across Asia to western Siberia. Introduced to North America, where it has escaped from gardens and spread widely.
- Preferred conditions
- Prefers full sun to part shade and moves readily into disturbed soil.
- Flowering
Flowers Jul–Sep
Flowers Jul–Sep
Growing it
- Propagation
- Spreads both by seed and by creeping rhizomes.
- Toxicity
- Roots and leaves are rich in , the foaming compounds. Eating large amounts can cause nausea, vomiting, and diarrhea.
Name and classification
- Varieties and forms
- Double-flowered garden forms are grown, and double flowers also turn up on escaped plants.
Conservation
- Conservation
- Washington State keeps it on its weed board's monitor list rather than its official list.
Culture and stories
- Culture and stories
- The genus name Saponaria comes from the Latin sapo, "soap"; the word "saponin" has the same root.
- Water boiled with the leaves or roots cuts grease, and it was long used as a gentle wash for delicate woolens.
- In the Middle East the root is added when making halva, and some commercial tahini makers use the plant as an emulsifier.
More species to explore
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