In their natural habitats, Sempervivums grow near rocks on shallow soils under harsh conditions. For example, Sempervivum arachnoideum, the wonderful cobweb sempervivum, is a Western European native that grows in rocky areas on shallow soils subject to heat, cold and drought. The ability to withstand these conditions is what makes it such a tough, easy-to-grow plant.
To identify suitable companion plants, we like to consider a plant's natural habitat. Plants that grow with Sempervivum arachnoideum in nature include other hens and chicks, sedums and familiar rock garden plants, such as Rock Speedwell and Rock Campion. In general, good candidates to grow with sempervivum are plants that need lean, infertile, well-drained soil, sun to partial sun, and low to moderate water.
Other succulents, such as Jovibarba heuffelii, Sedum hispanicum, Sedum sexangulare, and Sedum rupestre, are frequently found growing with sempervivum. They make great companion plants because they all share shallow root systems and drought tolerance. Those very traits are what make the plants successful at growing in difficult situations. In fact, we recommend using hens and chicks and other succulents in the spaces between rocks to help keep soil in place in newly built rock and crevice gardens as well as in rock walls.
Drought tolerant and sun-loving cushion plants like Cushion Pink (Dianthus subacaulis), Pussytoes ( Antennaria media), and Miniature Yarrow (Achillea ageratifolia) are also good choices. In addition, some Dianthus prefer partial shade, and these can be placed on the north or the east side of rocks for protection from the harshest rays. The attractively mounding Draba cusickii, Spring Gentian Gentiana angustifolia, with its fabulous gentian blue flowers, and Lynn's favorite, a silver Saxifrage called Saxifraga 'Whitehill,' all need a little extra protection from summer heat.
Mat-forming plants, including Creeping Thyme Thymus serpyllum and Raoulia australis, create an interesting effect when grown among Jovibarba and Sempervivum rosettes. One example of this can be found in our display gardens, where a small-mounded crevice garden is ringed by a collection of small-rosette Sempervivums, while Jovibarba hirta is tucked into crevices and a spreading mat of Raoulia australis creeps along an exposed southwest slope.
Spring-flowering bulbs that are dormant in summer also work well as Sempervivum companion plants. Examples of sun-loving, spring-flowering bulbs include miniature Narcissus 'Little Gem' and Narcissus 'Minnow' and dwarf Tulips like Tulipa bakeri 'Lilac Wonder,' as well as Western native bulbs Camas Camassia quamash and Triteleia 'Corrina.' These can be kept quite dry during dormancy and are perfect in areas that do not receive supplemental water in summer.
You can even use low shrubs like Northwest native Penstemon cardwellii, small-leaf Hebe 'Red Edge,' and sun-loving dwarf conifer Pinus mugo 'Donna's Mini.' In one of our bermed gardens, several Sempervivum plants have grown to fill the space between a large shrubby Penstemon and a Sedum rupestris groundcover to form an attractive combination.
As you can see, there are many potential companion plants for Sempervivums that will help create a visually interesting and varied garden. Just remember Sempervivums are alpine, rock-garden plants in their native habitat. Along with Lynn, you can use this fact to inspire your own gardens.
Wild Ginger Farm
Owned and operated by Emma Elliott & Truls Jensen
Emma Elliott has always loved plants, whether found in the garden or discovered on a hike. She is the driving force behind the gardens at Wild Ginger Farm. Emma has also discovered a second love: photographing plants and researching information about them. She created and maintains the Wild Ginger Farm website, sharing photos and plant descriptions, as well as garden ideas, with visitors. Her goal is to inspire others to learn about and grow uncommon plants and to create naturalistic garden spaces.
Truls Jensen was born in Norway and, after moving to the US as a child, was drawn to the Sierra Nevada of California, where he explored and backpacked extensively. His interest in nature led him to study biology and ultimately to earn a PhD in Entomology. As a scientist he conducted ecological field research for the University of California, the United States Department of Agriculture, and the Illinois Natural History Survey. Truls brings his observational skills to his role as primary propagator at Wild Ginger Farm. His ability to think outside the box has led to innovative propagation and cultivation approaches.