Sempervivum
Sempervivum tectorum
Grit rather than mulch, sun rather than shade, and almost no water at all — flowered rosettes are simply pulled away when they finish.
Spacing & sowing
- Plant spacing
- 5.9 in
- In-row spacing
- 5.9 in
- Between rows
- 7.9 in
- Square-foot density
- Not suited to SFG
Growing
- Type
- Shrub · Perennial
- Botanical family
- Mixed / other
- Sunlight
- Full sun for the best color and the tightest form.
- Watering
- Almost none; overwatering is what kills it.
- Feeding
- Keep feeding minimal; too much makes soft growth.
- Frost tolerant
- Yes
- Flowering
- June
- Pruning
- Pull off the dead flower stalks and the spent rosettes.
Through the year
- Mar–Jun Spring Growth
- Jun–Aug Flowering
- Aug–Nov Growing
- Nov–Dec Leaf Fall
- Jan–Mar Leaf Fall
Companions
Sedum, Thyme, Saxifrage, Aubrieta
Pests & problems
- Mealybugs White cottony sap-suckers that gather in leaf axils and along stems, mostly on houseplants and under glass. Dab colonies with a cotton swab dipped in soapy water and isolate affected plants.
- Vine weevil Adults notch leaf edges at night; their plump C-shaped grubs devour roots, especially in containers. Hand-pick adults after dark and water in biological nematodes in late summer.
- Root & crown rot Roots or crown turn brown and mushy in waterlogged soil or compost; the plant wilts even when wet. Improve drainage, water less, and pot up only into free-draining mixes.
Garden allies
Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant
- Beneficial nematodes Steinernema & Heterorhabditis spp.Hunts Vine weevil
Microscopic worms watered onto damp soil that hunt down soil-dwelling grubs and release a bacterium that kills them within days. Timing is the whole thing: warm, damp soil and a small target grub, which means late summer for most of what they are used against.
- Frogs & toads AnuraHunts Vine weevil
A resident toad works the beds every night for slugs, cutworms, and weevils. Recruit them with water — even a sunken basin pond — plus damp shade and an upturned-pot toad house; skip the slug pellets that poison their prey.
- Green lacewing Chrysoperla carneaHunts Mealybugs
Its bristly larvae — "aphid lions" — impale aphids, mealybugs, thrips, and mite colonies, eating hundreds a week. Adults feed on nectar and pollen from small open flowers and overwinter in hollow stems left standing.
- Ground beetle CarabidaeHunts Vine weevil
Fast, glossy night hunters that patrol the soil surface for slugs, cutworms, and root-fly larvae. Give them daytime cover — thick perennial edges, stepping stones, a log — and skip the tillage that wrecks their burrows.
- Hedgehog Erinaceus europaeusHunts Vine weevil
A European animal, and worth saying so plainly: there are no hedgehogs in North America, and the ally that does the same night shift here is the toad, the opossum or the ground beetle. Where they do occur, cut a gap in the fence and skip the pellets.
- Hoverfly SyrphidaeHunts Mealybugs
Bee-mimicking flies whose legless larvae graze aphid colonies clean while the adults pollinate. A ribbon of shallow, nectar-rich flowers kept in bloom all season recruits wave after wave of them.
- Ladybird (lady beetle) CoccinellidaeHunts Mealybugs
The gardener’s favorite ally: adults and their alligator-shaped larvae each eat thousands of aphids, plus scale, mealybugs, and other soft-bodied sap-suckers. Grow flat, open flowers for the adults and never spray a colony that ladybird larvae are already working.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com