Soapwort is a cottage garden favorite known for its profusion of dainty blooms and vigorous growth habit.
Available in many shades of pink and white, these tiny flowers are reminiscent of phlox blossoms.
Soapwort flowers have a lovelysweet smellthat is especially fragrant on cool evenings.
Credit: Peter Krumhardt
Additionally, soapwort is mildly toxic to humansand livestock.
While soapwort can grow in rocky and sandy soils, lean, well-draining garden soil is best.
Low-growing varieties of the plant look good spilling over walls inrock gardens, troughs, and containers.
Credit: Peter Krumhardt
Taller varieties work well mixed with other tough perennials.
Sow soapwort seeds in a prepared bed in early spring immediately after the last frost.
The seeds benefit from a period of cold before they germinate.
Credit: Peter Krumhardt
Dont amend the soil to make it rich; the plant does better in lean soil.
However, if the soil lacks good drainage, amend it withcompost.
Press the seeds lightly into the soil but dont cover them.
Credit: Marty Baldwin
When they germinate, thin them to 1 foot apart.
You might be able to purchase nursery-grown plants that go into the ground after the last frost in spring.
Dig holes in a prepared bed just large enough for the transplants and space them 1 foot apart.
Credit: Marty Baldwin
Soapwort Care Tips
Soapwort is easy to grow and requires little hands-on care after it is established.
Light
Plant soapwort infull sunto encourage compact growth and maximize blooming.
Lean soil reduces unwanted spreading.
Credit: Marty Baldwin
In extremely cold areas, apply a layer of mulch around the plants in winter to protect the roots.
Soapwort does not grow well in hot, humid environments.
Alternatively, spread homemade compost around the base of the plant.
Credit: Peter Krumhardt
Dont overfertilize; the plant grows best in lean conditions.
The container must provide excellent drainage as soapwort cant stand soggy roots.
How to Propagate Soapwort
Soapwort can be propagated through seeds, divisions, and stem cuttings.
Seeds
Soapwort self-seeds prolifically.
Break pop pop the blooms to harvest the seeds.
you’re able to alsosow seeds indoorsin winter for transplants for the following spring.
Germination takes about three weeks.
Divisions
Soapwort spreads itself by underground rhizomes.
Replant the divisions immediately into a prepared garden bed and water them.
Spring or fall is the best time of year for soapwort divisions.
Cuttings
Takestem cuttingsfrom soapwort in late fall.
Remove all but the topmost leaves and dip the stem in arooting hormone powder.
Put the container in a cool area with bright light.
When new growth appears, the stem has rooted.
After a robust root system develops, the cutting can be transplanted to the garden.
The flowers are held in loose clusters on sturdy 2-foot stems with knots at the nodes.
Some forms have variegated foliage.
Zones 3-9 are ideal for this variety of soapwort.
It grows 6-9 inches tall and is hardy in Zones 4-8.
Soapwort Companion Plants
Veronica
Easy and undemanding,veronicacatches the eye in sunny gardens.
Provide full sun and average well-drained soil.
Regular deadheading extends bloom time.
Balloon Flower
Balloon flowermakes excellent cut flowers.
Balloon flower tolerates light shade but not wet feet or drought.
Well-drained but moisture-retentive soil is a must for this prairie native.
Many of the best cultivars are hybrids, and all are excellent for cutting.
Deadhead to extend bloom time and divide the clumps every couple of years to ensure vigor.
Frequently Asked Questions
This hardy perennial will grace the garden for years.
Soapwort (Bouncing Bet).
Missouri Department of Conservation.
Soapwort - Saponaria officinalis.
Saponins.Cornell College of Agriculture and Life Sciences.
Midwest Invasive Plant List.
Midwest Invasive Plant data pipe.
