These three hardy succulents are some of the most diverse of all plants; some are miniatures, like Sedum album 'Faro Form' and tiny Sempervivums. There are also varieties of Sempervivums with medium to larger growth habits.
They originate high up in mountain crags, with intense ultraviolet light exposure, and short summers.
Some of them continue to grow, although slowly, though the winter months even covered in snow.
Generally, hardy succulents have a preference for a sunny aspect, with well drained sandy or gravelly soil; don't try and grow them in waterlogged organic soils; they will quickly rot.
They have no adaptation for dealing with excess water, especially in the early spring.
They benefit from a small amount of steer manure when planting into their final destination, and a mulch of pebbles, lava rock or other mineral mulching material. Don't use bark mulch, wood chips or pine needles; any mulch that retains moisture around the crown, or is too acidic will not make them happy, and can cause rotting of the base of the plant.
Jovibarba are sometimes classed as another species of Sempervivum; other times, they are listed as a separate genus. Either way, these little known and incredibly hardy succulents deserve to be more widely grown.
The smaller species Jovibarba are generally spiky (but soft) little clustering plants, also called 'rollers' for their habit of holding their children high above their heads, to release them to let them roll away and form a new colony.
The tiny propagules, or chicks, are perfectly suited to this rather distinctive form of population expansion, because they are almost completely round. They also have an adaptation to turn themselves over, and end up root side down, where they can put down roots for a happy existence in a clustering colony.
The other less well known Jovibarba heuffelii, otherwise known as 'huffies' are a different creature altogether. These odd and unusual plants grow as a thick caudex or crown, which splits at the surface to create a tightly knit mat. These are considerably more expensive to obtain, because they have to be surgically separated to create more plants.
They are well worth the trouble to find, because they are so unique and different.
Your garden deserves some hardy succulents to provide carpets of interesting foliage, in all colors of the rainbow. These easy to grow plants are a xeriscapers dream; tough, reliable, drought tolerant, and beautiful.