UK compost
What compost for ram's head catasetum in the UK?
Catasetum arietinum
More about ram's head catasetum in the UK
Which compost ram's head catasetum needs
For ram's head catasetum the mix to buy is peat-free multipurpose compost. Fine-grade orchid bark with perlite works well for this species; sphagnum moss is also used successfully as it retains water and fertilizer effectively for heavy summer feeding. Grow in baskets or well-drained pots. Repot annually in spring when new growth initiates.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 ram's head catasetum 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?
Ram's Head Catasetum is straightforward: an ordinary peat-free multipurpose compost is right. For a big specimen or a pot it will live in for years, mixing in some loam-based John Innes No.2 or No.3 adds weight and holds nutrients longer. Ericaceous compost is not needed unless a plant is specifically a lime-hater.
For the full recipe, pH and drainage detail (US wording), see the ram's head catasetum soil & potting-mix guide.
Compost for Ram's Head Catasetum in the UK — frequently asked questions
What compost should I use for ram's head catasetum in the UK?
Use peat-free multipurpose compost. Fine-grade orchid bark with perlite works well for this species; sphagnum moss is also used successfully as it retains water and fertilizer effectively for heavy summer feeding. Grow in baskets or well-drained pots. Repot annually in spring when new growth initiates. 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 ram's head catasetum?
Yes. A good peat-free multipurpose compost is exactly right for ram's head catasetum. For a large or long-term pot you can mix in some John Innes No.2 or No.3 (loam-based) for extra weight and staying power.
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 ram's head catasetum perfectly well — they dry a little faster at the surface, so check moisture by feel rather than by the look of the top.
Does ram's head catasetum need grit or perlite added?
Not essential, but a couple of handfuls of perlite in the mix improves aeration and guards against overwatering — useful on a cool, damp British windowsill where compost stays wet longer.
What pot and drainage does ram's head catasetum need?
Always a pot with drainage holes. Fine-to-medium bark or sphagnum with excellent drainage. 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 ram's head catasetum care
See the full ram's head catasetum care guide, its UK watering and UK hardiness.