Pocket BotanistPlant guide
Common soapwort.
Saponaria officinalis
Pronounced sap-oh-NAIR-ee-uh oh-fiss-ih-NAH-liss
Also known as Bladder Soapwort, Bouncing Bet, Bouncingbet, Bouncingbet Soapweed, China Cockle, Common Soapwort, Cow Basil, Cow Foot
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Soapwort is a charming perennial that was historically used to create a natural soap from its roots and leaves. It spreads quite easily through underground runners, making it a great choice for naturalizing in larger garden spaces. You will love its clusters of fragrant, pale pink or white flowers that bloom throughout the summer.
At a glance
- Care level
- Easy
- Plant type
- Perennial
- Light
- Full sun to partial shade
- Indoor light
- Direct sun
- Water
- Every 3 to 7 days
- Mature size
- 2 to 3 feet tall
- Growth rate
- Fast
- Hardiness
- USDA 3 to 9
- Bloom time
- Mid summer to early autumn
Care
Plant this in a spot where it has room to spread, as it can become quite vigorous. Keep the soil consistently moist but avoid letting it sit in water. Watch for powdery mildew on the leaves during humid spells and simply trim back spent stems to encourage a second flush of blooms.
- Watering
- Water whenever the top inch of soil feels dry to the touch.
- Feeding
- Apply a balanced liquid fertilizer once every two months during the active growing season.
- Pruning
- Deadhead faded flowers to keep the plant tidy and prevent unwanted self seeding.
- Repotting
- Divide the root clumps every couple of years to keep the plant vigorous and contained.
- Soil
- Well draining, fertile soil
- Soil pH
- 6.0 to 7.5
- Temperature
- -30 to 35°C
- Humidity
- 40 to 70%
Safety
- People
- All parts of the plant are toxic if ingested and can cause digestive irritation.
- Pets
- This plant is considered toxic to cats and dogs if ingested.
- Children
- Keep this plant away from children as ingestion of any part can lead to stomach upset.
- Contact allergens
- Handling the plant may cause skin irritation in sensitive individuals due to saponin content.
- Airborne allergens
- The pollen may cause mild reactions in those with severe allergies.
- Edibility
- This plant contains saponins and is not considered edible.
How to identify it
- Opposite, oval shaped leaves
- Clusters of five petaled flowers
- Flowers range from white to pink
- Stems are smooth and upright
- Grows from creeping underground rhizomes
- Height
- 0.3 to 0.9m
- Spread
- 0.3 to 0.6m
- Leaves
- green, deciduous
- Flowers
- pink, white, 2 to 3cm
Problems to watch for
- Powdery mildew · A fungal growth that appears as white dust on the leaves during humid weather.
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Growing it
- Propagation
- division, seed, cuttings
- When to plant
- spring, autumn
Plant in a contained area to prevent it from outcompeting neighboring perennials.
Grows well with
- Lavender · They share similar sun and soil requirements.
- Catmint · It provides a lovely contrasting texture and color.
Similar species
- Campion · They belong to the same family and share similar flower structures.
Science
- Family
- Caryophyllaceae
- Genus
- Saponaria
- Order
- Caryophyllales
- Class
- Magnoliopsida
- Native range
- Europe and parts of Asia.
- Conservation
- It is considered an invasive species in some regions of North America.
It thrives in disturbed soils and along stream banks where it can spread through its vigorous root system.
- Value to wildlife
- nectar source
- Pollinators
- moths, bees, butterflies
- Uses
- ornamental, historical cleaning agent, pollinator garden
Through the year
Ecological indicators
- Salinity
- 2/9
- Soil reaction
- 6/9
- Light
- 7/9
- Temperature
- 5/9
- Moisture
- 5/9
- Nutrients
- 5/9
Taxonomy resolved against GBIF.
Questions people ask
- Is it easy to grow?
- Yes, it is very hardy and often spreads aggressively.
- Does it need full sun?
- It prefers full sun but tolerates partial shade.
Where the name comes from
The name Saponaria comes from the Latin word sapo, meaning soap, referring to the lathering properties of the roots.
Good to know
- It is also known as soapwort.
- The plant spreads via underground rhizomes.
- It has been used in restoration of old textiles.
Also in
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This guide was generated with AI on and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.