UK compost
What compost for sempervivum 'pacific blue ice' in the UK?
Sempervivum 'Pacific Blue Ice'
More about sempervivum 'pacific blue ice' in the UK
Which compost sempervivum 'pacific blue ice' needs
For sempervivum 'pacific blue ice' the mix to buy is peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Plant in cactus/succulent compost cut about 1:1 with grit, pumice, or perlite. A lean, neutral, sharply draining substrate prevents the crown sitting wet and helps preserve the cool, glaucous bloom on the leaves.In British garden centres the bagged growing medium is sold simply as “compost” (multipurpose, ericaceous, or loam-based John Innes), which is a different thing from the rotted garden “compost” you make in a heap — for a pot you want the bagged kind.
Peat-free compost
Buy peat-free. The sale of peat compost to home gardeners is being phased out across the UK, and the RHS recommends peat-free on environmental grounds. A good peat-free multipurpose grows sempervivum 'pacific blue ice' perfectly well; the one habit to change is watering — peat-free dries faster at the surface while still moist below, so check by feel a knuckle deep rather than trusting the look of the top.
Ericaceous or multipurpose?
Sempervivum 'Pacific Blue Ice' does not want a rich, water-holding compost — it wants sharp drainage. Cut peat-free multipurpose roughly half-and-half with horticultural grit, sharp sand or perlite, and always pot into a container with drainage holes. A "cactus and succulent" bagged mix is a ready-made shortcut.
For the full recipe, pH and drainage detail (US wording), see the sempervivum 'pacific blue ice' soil & potting-mix guide.
Compost for Sempervivum 'Pacific Blue Ice' in the UK — frequently asked questions
What compost should I use for sempervivum 'pacific blue ice' in the UK?
Use peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Plant in cactus/succulent compost cut about 1:1 with grit, pumice, or perlite. A lean, neutral, sharply draining substrate prevents the crown sitting wet and helps preserve the cool, glaucous bloom on the leaves. In UK garden centres this is sold simply as "compost" — the bagged growing medium, not garden-made leaf-mould — so match the description above rather than a brand.
Can I use ordinary multipurpose compost for sempervivum 'pacific blue ice'?
Not on its own — multipurpose compost holds too much water for sempervivum 'pacific blue ice' and will rot the roots. Cut it roughly 50:50 with horticultural grit, sharp sand or perlite so it drains fast.
Should the compost be peat-free?
Yes. Sales of peat compost to home gardeners are being phased out in the UK, and the RHS recommends peat-free for environmental reasons. Modern peat-free multipurpose composts grow sempervivum 'pacific blue ice' perfectly well — they dry a little faster at the surface, so check moisture by feel rather than by the look of the top.
Does sempervivum 'pacific blue ice' need grit or perlite added?
Yes — sempervivum 'pacific blue ice' must have sharp drainage. Add about one part horticultural grit or perlite to one part compost, and always use a pot with drainage holes.
What pot and drainage does sempervivum 'pacific blue ice' need?
Always a pot with drainage holes. Gritty, fast-draining succulent mix. Stand it on a saucer, empty any water that collects after watering, and never leave the pot sitting in a full outer cover — waterlogged compost in a cool UK room is the commonest cause of root rot.
More sempervivum 'pacific blue ice' care
See the full sempervivum 'pacific blue ice' care guide, its UK watering and UK hardiness.