Orostachys (or-oh-STACK-eez) is a genus of frost hardy succulents somewhat similar to Sempervivum and Sedum. They grow clustering rosettes with gorgeous, round foliage. Their flowers are tall, conical inflorescences that give them the common name "dunce caps". Read on for helpful succulent care tips.
- Light: Most hardy succulents require lots of light, so aim to grow them outdoors in full to partial sun, with more shade when temperatures exceed 85F. To grow indoors, keep them on a sunny window sill or use dedicated grow lights, though you may still see them fade to green and stretch. Succulents recently shipped in a box will need up to two weeks to gradually adjust to full, outdoor sun. More info.
- Soil: Like most succulents, hardy varieties grow best in well-draining, gritty soil. Most garden centers sell a cactus/succulent potting soil, or you can add sand to your own soil mix to make a sandy loam. None require fertilizer, but a slow-release, low-Nitrogen (5-10-10) application in the spring will encourage faster growth.
- Water: A cycle of deep soaking followed by time for the soil to fully dry will lead to healthy root development. Young plants will need more frequent watering to establish roots, whereas less water is preferable in winter. When planting in a container, be sure to use a pot with a drainage hole. More info.
- Hardiness: Most of the varieties listed here tolerate deep freeze down to at least -20F (zone 5). Sempervivum heuffelii and many Sedum can tolerate -30F (zone 4). A blanket of snow will protect hardy succulents from winter exposure, but in snow-free regions gardeners can use clear covers and bring potted succulents under shelter to prevent standing water and rot. More info.
- Propagation: No propagation work is necessary for any of these varieties, but specific instructions on multiplying and transplanting each type are included in their respective category descriptions.
NOTES FROM THE NURSERY
Hardy succulents are adapted to harsh alpine habitats, so it's not surprising that they're such resilient growers in the garden. They are considered "Old World Treasures" and in the Middle Ages were planted on rooftops to ward off lightning. Their presence on roofs continues today in the form of ecologically sustainable green roofs, because they grow so well in shallow soil with little to no maintenance.
Hardy succulents make excellent landscaping and container plants, no matter your level of experience. Try planting them in rock walls, around stepping stones, and in other nooks and crannies around the garden.