Growing Sedum Ternatum: Caring For Woodland Stonecrop

Sedum ternatum [SEE-dum, ter-NAY-tum] is an herbaceous perennial and native plant in North America, it is found in the United States in Arkansas, Georgia, Missouri, and Iowa. 

The native ternatum sedum is also found down south in the Appalachian Mountains, near the Canada-US border in the north, and throughout the eastern United States.

Flowers of the Woodland Stonecrop (Sedum ternatum)
Image by David J. Stang [CC BY-SA 4.0], via Wikimedia Commons

Within the Sedum plant genus, this species is considered one of the most widespread. 

It belongs to the stonecrop family Crassulaceae.

The common name “stonecrop” comes from the plant’s ability to thrive atop stones and boulders. 

Other common names include:

  • Wild stonecrop
  • Iceland moss
  • Three-leaved stonecrop

The latter referring to the leaves which appear in whorls of three.

This sedum is known for their plump succulent leaves and white flowers blooming from April to May. 

It’s often used in landscaping in shady spots and in pots.

Sedum Ternatum Plant Care

Size & Growth

Ternatum features small, fleshy leaves about ¾” inch long. The rounded succulent-like bright green leaves appear in whorls of three.

Growing under the best condition, these plants may grow 3” – 6” inches high. 

But the main attraction besides the flowers is the spread, which is approximately 10” inches wide. 

The stems creep and root rapidly during the growing season, dying back in the winter. New plants are left behind for the next season.

Flowering and Fragrance

The showy star-shaped white flowers add to the beautiful foliage. The bloom time lasts from April to May or from late spring to early summer. 

During this time, Sedum Ternatum produces clusters of small white star-like flowers. They appear on erect stems, rising above the foliage.

Each flower is about half an inch wide with four petals and purplish stamens. 

The blooms attract butterflies for pollination.

Light & Temperature

Native to Easters US and other North American locations, these plants are hardy to USDA Hardiness Zones 4 to 8. 

Ternatums are survivors and thrive in conditions where other plants wouldn’t.

Grow Iceland moss in a location with full sun or in partial shade for best results.

Watering and Feeding                                             

Since wild stonecrops are succulents, they have moderate watering requirements. 

You don’t have to water them too often. 

Just make sure the soil has sufficient moisture and doesn’t dry out completely.

These plants prefer lean conditions. 

Go easy on the fertilizer. 

Use organic compost or a succulent formula in small quantities. 

Excessive feeding can lead to flopping and leggy growth.

Soil & Transplanting

Soil mixtures for succulents are the optimal choice. 

These plants are easy to grow and will thrive in average, rocky soils with medium moisture and good drainage. 

This particular species of the Sedum genus is very hardy. 

It is not only deer-resistant but also tolerates soil moisture better than other species.

As for transplanting, simply cut the stem or rhizomes and push in a safe location. 

Or plant it in individual pots where they will root easily.

Grooming and Maintenance

Grooming and maintenance are at its minimum with the wild stonecrops. 

Once it has established its roots, it grows in the prostrate position on the ground and stones. 

Moving on, the only maintenance you need to provide is concerned majorly with removing unwanted or damaged plants.

How To Propagate Wild Stonecrop Plant

The best way to propagate these plants is through division. 

Separate offsets from the rhizomes and plant them in their permanent location under part shade. 

Take cuttings from the stem. 

You don’t need a rooting chamber.

Optionally start the plants with seeds. 

Start by collecting the seeds from 2 to 3 weeks after the plants have flowered. 

Air dry and treat them to cold stratification in sealed containers. 

Since the seeds are so small, mix them with sand and sow them in a protected location.

Woodland Stonecrop Plant Pest or Diseases

Like other Sedum species, S. ternatum is not affected by serious insect or pest and disease problems. 

However, the one the plant may be susceptible to include botrytis.

Botrytis, which is only an occasional problem, spreads through creeping stems. It is a type of fungus or gray mold appearing on the leaves. 

If your plant is affected by it, remove the diseased plant to prevent it from spreading.

Other problems to keep an eye out for include powdery mildew, rusts, southern blight, stem rot, and some other mold diseases. 

These may be caused by excessive water near the rhizomes. 

Avoid overwatering the plants to prevent some of these problems.

Sedum Ternatum Plant Uses

Growing in partial shade and full shade, these plants are most viable combined with other semi-shade loving plants such as the Dwarf Crested Iris (Iris cristata) in shade gardens around your home. 

Use this stonecrop family member as a ground cover in fields, rock gardens, and flowerbeds.

Besides native plant gardens, these succulents look great potted and placed around porches. 

While it’s mostly used for ornamental purposes, woodland stonecrops do attract pollinators – specifically moths and butterflies.