Sempervivum montanum subsp. stiriacum is an ornamental, evergreen, perennial succulent. It grows up to 10 cm (4 inches) tall, distinguished from Sempervivum montanum by its slightly narrower, brown-tipped leaves. It produces tight, rounded rosettes of tiny, fleshy, dull green leaves with pointed, maroon-brown tips. The rosettes multiply via short-stalked offsets to form dense mats. In summer, some older rosettes bear clusters of relatively large, starry, purple-pink blooms on thick erect scaly-leaved stalks. The blossoms have conspicuous white highlights. Rosettes that flower dies soon thereafter.
Scientific Name: Sempervivum montanum subsp. stiriacum (Wettst. ex Hayek) Wettst. ex Hayek
Synonyms: Sempervivum stiriacum (basionym), Sempervivum braunii, Sempervivum funckii, Sempervivum montanum f. braunii, Sempervivum montanum var. braunii, Sempervivum montanum var. stiriacum
Common Names: Mountain Houseleek, Anomalous Houseleek
How to grow and maintain Sempervivum montanum subsp. stiriacum:
It thrives best in full sun to light shade. In indoor an east or west-facing window where they receive four to six hours of sunlight is ideal.
It grows well in a well-drained succulent mix, with an ideal pH around 6.0 (slightly acidic) or an equal part sharp sand with all-purpose potting mix.
Water regularly during the summer and spring. keep the soil evenly moist but not soggy. You can allow the topsoil to become slightly dry between each watering. Reduce water in the winter.
It prefers an average summer temperature 65 degrees Fahrenheit – 70 degrees Fahrenheit / 18 degrees Celsius – 21 degrees Celsius. In winter, some varieties can withstand temperatures down to freezing.
Fertilize with a controlled-release fertilizer at the beginning of the season or weekly with a weak liquid solution. Use a balanced 20-20-20 fertilizer at 1/4 strength on mature plants, and a fertilizer with less nitrogen on young plants.
Re-pot as needed, preferably during the warm season. To re-pot, a succulent, make sure the soil is dry before repotting, then gently remove the pot. Knock away the old soil from the roots, making sure to remove any rotted or dead roots in the process. Treat any cuts with a fungicide. Place the plant in its new pot and backfill with potting soil, spreading the roots out as you re-pot. Leave the plant dry for a week or so, then begin to water lightly to reduce the risk of root rot.
Pests and Diseases:
It has no serious pest or disease problems. Mealybugs can be a problem, and if dead leaves are not expelled from the plant, it can attract other insect pests or have problems with fungus.
It can be easily propagated by offset. Sempervivum earned their famous name “Hen and Chicks” from their growth habit. The mother plant, or hen, sends off numerous offsets, which will cluster around her base like chicks. These offsets can be easily re-potted, or the plants can be left to form a clumping mat.