Garden flowers

Houseleek

SempervivumCrassulaceae
Also: Hens and chicks, Sempervivum
AT A GLANCE
Full sun Water: little H7below −20 °C 5–10 cm tall · 10–15 cm wide In a pot: yes
Flowering · UK
Flowering · Northern Italy
Flowering · Central Italy
Flowering · Southern Italy and islands

Plant in gritty, free-draining compost from the start and avoid watering unless the compost is fully dry — fails far more often from overwatering than neglect.

Care

Light

Full sun.

Water

Highly drought-tolerant; dislikes winter wet far more than cold.

Soil

Very free-draining, gritty, poor soil; excellent in shallow pans, troughs, rockeries and green roofs.

Pruning

No routine pruning; remove spent flower rosettes after they die back (each rosette flowers once then dies, producing offsets — 'chicks' — around it).

Feeding

Never feed. These live on rock and roof tiles; fertiliser makes them soft, green and loose, losing exactly the tight red-tinged rosette they are grown for.

Propagation

Pull off the offsets — the little rosettes on runners round the parent — and press them onto gritty compost. Most have already made roots before you detach them, so they establish immediately, and the parent rosette dies after flowering anyway.

Month by month

Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.

  1. MarchTop-dress with grit if compost has become compacted. how ›
  2. JuneRemove any flowered (dying) rosettes to make room for offsets. how ›
  3. SeptemberSeparate and replant offsets to fill gaps or start new pots.

Months based on climate: UK. Your choice stays on this device.

  1. MarchTop-dress with grit if compost has become compacted. how ›
  2. JuneRemove any flowered (dying) rosettes to make room for offsets. how ›
  3. SeptemberSeparate and replant offsets to fill gaps or start new pots.

Months based on climate: Northern Italy. Your choice stays on this device.

  1. FebruaryTop-dress with grit if compost has become compacted. how ›
  2. JuneRemove any flowered (dying) rosettes to make room for offsets. how ›
  3. SeptemberSeparate and replant offsets to fill gaps or start new pots.

Months based on climate: Central Italy. Your choice stays on this device.

  1. FebruaryTop-dress with grit if compost has become compacted. how ›
  2. JuneRemove any flowered (dying) rosettes to make room for offsets. how ›
  3. OctoberSeparate and replant offsets to fill gaps or start new pots.

Months based on climate: Southern Italy and islands. Your choice stays on this device.

Common problems

Rot from winter wet

How to spot it. Mushy, collapsing rosettes.

What to do. Ensure sharp drainage; avoid saucers that trap water under pots — the main risk for this otherwise tough genus.

Vine weevilfull sheet ›

How to spot it. In compost.

What to do. Check compost periodically.

How to spot it. In the crevices between leaves.

What to do. Treat if noticed.

Popular varieties

Sempervivum ‘Arachnoideum’AGM5–8 cm × 15–20 cm · June–JulyJune–JulyMay–JulyMay–July
Sempervivum ‘Commander Hay’10–15 cm × 20–30 cm · June–JulyJune–JulyMay–JulyMay–July
Sempervivum ‘Jubilee’8–10 cm × 20 cm · June–JulyJune–JulyMay–JulyMay–July
Sempervivum ‘Othello’8–12 cm × 15–20 cm · June–JulyJune–JulyMay–JulyMay–July

Questions

Houseleek: is it hardy?

H7: Fully hardy anywhere in the UK. It survives below −20 °C.

Can it grow in a pot?

One of the best genera for shallow pots, troughs and green roofs, precisely because it tolerates minimal soil volume.

Houseleek: when do you prune it?

No routine pruning; remove spent flower rosettes after they die back (each rosette flowers once then dies, producing offsets — 'chicks' — around it).

Houseleek: when does it flower?

In the climate of UK it flowers in June–July.

When do you feed it?

Never feed. These live on rock and roof tiles; fertiliser makes them soft, green and loose, losing exactly the tight red-tinged rosette they are grown for.