UK compost
What compost for tuberous begonia 'nonstop' in the UK?
Begonia x tuberhybrida 'Nonstop'
More about tuberous begonia 'nonstop' in the UK
Which compost tuberous begonia 'nonstop' needs
For tuberous begonia 'nonstop' the mix to buy is peat-free ericaceous (lime-free) compost. Use a peat- or coir-based potting mix with perlite for sharp drainage. Plant the tuber hollow-side up, just at the surface, since burying it deeply invites rot.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 tuberous begonia 'nonstop' 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?
Tuberous Begonia 'Nonstop' is a lime-hater: it needs an acidic, lime-free ericaceous compost. In ordinary (limey) multipurpose it slowly yellows between the leaf veins as it locks out iron. Buy a bag labelled "ericaceous", and in a hard-water area water with rainwater where you can, since tap water is slightly alkaline.
For the full recipe, pH and drainage detail (US wording), see the tuberous begonia 'nonstop' soil & potting-mix guide.
Compost for Tuberous Begonia 'Nonstop' in the UK — frequently asked questions
What compost should I use for tuberous begonia 'nonstop' in the UK?
Use peat-free ericaceous (lime-free) compost. Use a peat- or coir-based potting mix with perlite for sharp drainage. Plant the tuber hollow-side up, just at the surface, since burying it deeply invites rot. 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 tuberous begonia 'nonstop'?
No — tuberous begonia 'nonstop' needs an acidic, lime-free (ericaceous) compost. Standard multipurpose is too limey and will slowly cause yellowing between the leaf veins (lime-induced chlorosis). Buy a bag labelled "ericaceous".
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 tuberous begonia 'nonstop' perfectly well — they dry a little faster at the surface, so check moisture by feel rather than by the look of the top.
Does tuberous begonia 'nonstop' 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 tuberous begonia 'nonstop' need?
Always a pot with drainage holes. Light, free-draining, humus-rich 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 tuberous begonia 'nonstop' care
See the full tuberous begonia 'nonstop' care guide, its UK watering and UK hardiness.