UK compost
What compost for rigid draba in the UK?
Draba rigida
More about rigid draba in the UK
Which compost rigid draba needs
For rigid draba the mix to buy is peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Use a mix of 60% coarse grit or pumice, 20% loam, and 20% leaf mould. Neutral to slightly alkaline pH (6.8–7.5). The species originates in volcanic rock and scree, so open, mineral-rich compost is essential.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 rigid draba 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?
Rigid Draba 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 rigid draba soil & potting-mix guide.
Compost for Rigid Draba in the UK — frequently asked questions
What compost should I use for rigid draba in the UK?
Use peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Use a mix of 60% coarse grit or pumice, 20% loam, and 20% leaf mould. Neutral to slightly alkaline pH (6.8–7.5). The species originates in volcanic rock and scree, so open, mineral-rich compost is essential. 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 rigid draba?
Not on its own — multipurpose compost holds too much water for rigid draba 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 rigid draba perfectly well — they dry a little faster at the surface, so check moisture by feel rather than by the look of the top.
Does rigid draba need grit or perlite added?
Yes — rigid draba 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 rigid draba need?
Always a pot with drainage holes. Extremely sharply drained gritty or volcanic alpine 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 rigid draba care
See the full rigid draba care guide, its UK watering and UK hardiness.