Repotting guide

When & how to repot Large-Flowered Houseleek (Sempervivum grandiflorum)

Also called Large-flowered Houseleek, Big-flowered Hens and Chicks.

More about large-flowered houseleek

About Large-Flowered Houseleek

Sempervivum grandiflorum · also called Large-flowered Houseleek, Big-flowered Hens and Chicks · flowering

Sempervivum grandiflorum is a distinctive houseleek native to the subalpine and alpine zones of southwestern Switzerland and northwestern Italy, notable for its relatively large, star-shaped flowers with yellowish petals marked with a basal purple spot that appear in summer on stems up to 20 cm tall. Its rosettes reach up to 15 cm in diameter, spreading freely on leafy stolons to form dense mats. Like all houseleeks, it requires full sun and perfectly drained gritty soil, and the mother rosette dies after flowering but is replaced by numerous offsets. Sempervivum is listed as non-toxic to cats and dogs by the ASPCA.

Mature size: Individual rosettes up to 15 cm wide; flowering stems to 20 cm; mats spread indefinitely.

Watch for — Root and crown rot in waterlogged soil: Persistently wet soil, especially in winter, causes Phytophthora and Pythium root rots. Always plant in free-draining grit-based compost; raise beds or use troughs and apply a layer of grit as a surface mulch around the rosette neck.

How to tell large-flowered houseleek needs repotting

Repotting on a calendar is less reliable than reading the plant. For large-flowered houseleek, watch for these signs:

Roots growing out of the drainage holes, or the rootball lifting the plant proud of the rim.
Soil that has shrunk away from the pot sides and no longer holds water.
The pot is unstable because the plant has grown top-heavy.
Old, compacted, broken-down mix that stays wet too long — for a succulent that is a rot risk, so refresh it even if the pot size is fine.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot large-flowered houseleek

Every 2–3 years, into bone-dry mix. Large-Flowered Houseleek's growth habit — monocarpic, mat-forming succulent; rosettes spread via leafy stolons and the central rosette dies after flowering. — sets the pace. Sempervivum grandiflorum is a distinctive houseleek native to the subalpine and alpine zones of southwestern Switzerland and northwestern Italy, notable for its relatively large, star-shaped flowers with yellowish petals marked with a basal purple spot that appear in summer on stems up to 20 cm tall. Its rosettes reach up to 15 cm in diameter, spreading freely on leafy stolons to form dense mats. Like all houseleeks, it requires full sun and perfectly drained gritty soil, and the mother rosette dies after flowering but is replaced by numerous offsets. Sempervivum is listed as non-toxic to cats and dogs by the ASPCA.

What size pot to step large-flowered houseleek up to

Use a pot only one size up — or even the same pot with fresh gritty mix if the roots have room. Large-Flowered Houseleek stores water and rots in a large pot of slow-drying soil. A tight terracotta pot that dries fast is far safer than a generous plastic one. Never up-pot a succulent by several sizes.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot large-flowered houseleek

Spring or summer, while large-flowered houseleek is in active growth and warm, is best — roots recover fastest then, and the plant is not sitting in cool damp soil. Avoid repotting a succulent in winter dormancy.

Step-by-step: repotting large-flowered houseleek

Repot dry. Do not water large-flowered houseleek for several days first. Working with dry roots and dry mix dramatically lowers the rot risk for a succulent.
Pick a snug, fast-draining pot. Choose terracotta one size up at most, with a drainage hole. Have gritty gritty, well-drained, low-fertility mix ready.
Tip it out and clean the roots. Slide the plant out, crumble off the old soil, and trim any black, mushy or dead roots with clean snips.
Pot into dry mix. Set large-flowered houseleek at its original depth in dry gritty mix, firming gently. Do not bury the stem deeper than it was.
Wait a week before watering. Leave it completely dry and out of harsh sun for about 7 days so any damaged roots callus. Only then water lightly.

Aftercare

Keep large-flowered houseleek completely dry and out of fierce sun for about a week so any nicked roots callus before they meet moisture; watering a freshly repotted succulent is the classic way to rot it. Then resume the normal lean, dry rhythm. Do not fertilise for about 3 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for large-flowered houseleek

Large-Flowered Houseleek wants gritty, well-drained, low-fertility mix. Grow in a 50/50 blend of horticultural grit and loam-based compost, or a pre-mixed succulent compost. Rich, moisture-retentive soil causes soft growth and root rot. Suits troughs, rock gardens, scree beds, and roof plantings. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting large-flowered houseleek — frequently asked questions

How often should you repot large-flowered houseleek?

Every 2–3 years, into bone-dry mix for large-flowered houseleek. Repot large-flowered houseleek every 2–3 years into a snug pot of gritty, well-drained, low-fertility mix, ideally in spring or summer. Let it sit in dry soil and do not water for about a week afterwards so any nicked roots can callus. Over-potting and watering straight away is what rots succulents.

What size pot does large-flowered houseleek need?

When is the best time of year to repot large-flowered houseleek?

Should you water large-flowered houseleek after repotting?

No — not straight away. Repot large-flowered houseleek into dry mix and wait about a week before the first watering so any damaged roots callus over. Watering a freshly repotted succulent is the single most common way to rot one.

Should you fertilise large-flowered houseleek after repotting?

Not immediately. Wait about 3 weeks after repotting large-flowered houseleek. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.