UK compost
What compost for rose of sharon 'blue bird' in the UK?
Hibiscus syriacus 'Oiseau Bleu'
More about rose of sharon 'blue bird' in the UK
Which compost rose of sharon 'blue bird' needs
For rose of sharon 'blue bird' the mix to buy is peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Adaptable to most soils, including clay and slightly alkaline ground, at pH around 5.5-7.5. Best in moderately fertile, free-draining soil enriched with organic matter; it dislikes both bone-dry and persistently soggy sites.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 rose of sharon 'blue bird' 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?
Rose of Sharon 'Blue Bird' 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 rose of sharon 'blue bird' soil & potting-mix guide.
Compost for Rose of Sharon 'Blue Bird' in the UK — frequently asked questions
What compost should I use for rose of sharon 'blue bird' in the UK?
Use peat-free multipurpose compost cut roughly half-and-half with horticultural grit or perlite. Adaptable to most soils, including clay and slightly alkaline ground, at pH around 5.5-7.5. Best in moderately fertile, free-draining soil enriched with organic matter; it dislikes both bone-dry and persistently soggy sites. 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 rose of sharon 'blue bird'?
Not on its own — multipurpose compost holds too much water for rose of sharon 'blue bird' 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 rose of sharon 'blue bird' perfectly well — they dry a little faster at the surface, so check moisture by feel rather than by the look of the top.
Does rose of sharon 'blue bird' need grit or perlite added?
Yes — rose of sharon 'blue bird' 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 rose of sharon 'blue bird' need?
Always a pot with drainage holes. Moist, fertile, well-drained soil of average pH. 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 rose of sharon 'blue bird' care
See the full rose of sharon 'blue bird' care guide, its UK watering and UK hardiness.