The rock soapwort covers rocky surfaces with purple flower trails and provides plenty of food for insects during the flowering season between May and July.
Profile of rock soapwort:
Scientific name: Saponaria ocymoides
Plant family: pink family (Caryophyllaceae)
Other names: tumbling Ted
Sowing time: spring
Planting time: spring to autumn
Flowering period: May to July
Soil quality: stony to loamy, calcipholous, low in nutrients
These information are for temperate climate!
Use in: ground cover, planters, dry stone walls, rock garden, potted garden
Winter hardiness: hardy, USDA Plant Hardiness Zones: 4 (-32 °C / -25 °F)
Bee and insect friendly: Yes
Plant characteristics and classification of rock soapwort
Plant order, origin and occurrence of rock soapwort
The rock soapwort is a species from the genus soapworts (Saponaria). They all grow in meadows or rocky areas between Europe and Southwest Asia. Saponaria ocymoides has its home in the European mountains between Spain and the eastern Mediterranean up to an altitude of 2,000 meters (6,500 ft). The rock soapwort grows there on gravel and scree soils on embankments, river banks or in light forests. In North America the species is a neophyte. For many years Saponaria ocymoides has been used in rock gardens and for planting dry stone walls. It belongs to the pink family (Caryophyllaceae).
Characteristics of rock soapwort
The rock soapwort is a spreading perennial that forms extensive mats. The shoots develop lying down, rising or hanging. Saponaria ocymoides grows to a maximum height of 15 centimeters (6 in), which is why the plant is also known as small soapwort or tumbling Ted.
1 to 3 centimeters (0.4 to 1.2 in) long are the ovate-lanceolate, evergreen leaves of rock soapwort, which have lashes at the base. They have entire margins and short stems.
In summer, between May and July, whole carpets of 1 centimeter wide, pink to purple flowers open up and stand in clusters at the ends of the shoots. The sepals are fused into a tube, reddish-brown overflowing and glandular hairy. The petals are rounded or slightly indented at the edge. Two styles can be seen, the stamens protrude clearly. Insects, especially moths, like to visit the flowers.
Later, the capsule fruits, typical for pinks, develop and open with four teeth.
Rock soapwort – cultivation and care
Rock soapwort needs a full sunny location.
The rock soapwort needs a well-drained soil as in its natural habitat. It gets by with dry to fresh water conditions and low nutrient content. However, the soil should definitely be calcareous.
Planting rock soapwort
Where the ground is heavy, it is loosened up with coarse sand or gravel. Planting can be done at any time when the soil is not frozen.
Care / Watering / Fertilization
Watering is only necessary in the growth phase. A small amount of compost before flowering supports the joy of flowering. In order to prevent self-sowing, wilted parts should be cut back before the seeds are formed. To cut back, simply use scissors and cut off a third of the shoots. Wet fallen leaves should be removed, as the rock soapwort can literally suffocate under them in winter.
Before or after flowering, parts of the rootstock can easily be dug up and put in a new place in the ground. If the joy of flowering diminishes, the division acts like a fountain of youth. The oldest and thus outdated middle section is disposed of.
Sowing the species succeeds without problems in spring. Propagation by cuttings is recommended for the varieties. As with the lilacbush, outer new shoots can be covered with soil and then rooted young plants can be removed.
Diseases and pests
A too high nutrient content makes the shoots spongy and attractive for snails. Otherwise, the rock soapwort is very robust.
The plant is hardy down to -32 °C / -25 °F. A winter protection is not necessary.
Use in the garden
Wherever there is a slightly stony ground – rock garden, wall crown and the like – the rock soapwort finds its place. In the tub, Saponaria ocymoides inspires with its long flower trails.
- ‘Alba’ shines in pure white and is slightly less vigorous than the species.
- ‘Rubra compacta’ forms dense dark red mats.
- ‘Snow Tip’ grows about 20 centimeters (8 in) high. The pure white star-shaped flowers of this variety stand above dark green foliage.
- ‘Splendens’ blooms pinkish red.