Hibiscus requires bright, humid conditions with good ventilation, protected from direct sunlight and a minimum night temperature of 7ºC (45ºF). Plants can be placed outdoors in summer but need to be brought indoors before temperatures drop below 12ºC (59ºF).

Spring and summer

• Re-pot in February or early March using a peat-free, ideally one formulated specifically for houseplants.
  Soil based compost is a potting compost that includes sterilised soil/loam in the mix. As loam contains sand, silt and clay, it does not rot down like organic materials (including coir and peat), so adding soil/loam to compost ensures it is longer lasting - it is often used for shrubs in pots and will last 3-4 years without the need to be replaced.

  Soil based compost such as John Innes No 2 are also suitable
• Increase watering as the increasing light levels and temperatures stimulate growth
• Begin feeding weekly with a balanced liquid fertilizer for house plants, about six to eight weeks after re-potting

Overwintering

• A warm, humid glasshouse with minimum night temperatures of 7-10ºC (45-50ºF) is ideal, but a warm conservatory or south-facing windowsill will suffice
• Avoid placing plants near open fires, radiators or draughts and move away from windows in frosty weather
• Increase
  The amount of water vapour in the atmosphere. Different plants require different levels of humidity. Houseplants that need high humidity are best grown in a steamy bathroom, misted regularly or the pot placed in a saucer of damp pebbles. In a greenhouse, humidity can be raised in hot weather by damping down (wetting) the floor, overhead watering or misting. However, high humidity can cause fungal problems, in which case open vents to improve ventilation.

  humidity by placing the plant on a tray containing damp gravel or clay pellets. Plants can be grouped together to maintain a humid microclimate
• Reduce watering as growth slows and only water when the top layer of
  Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.

  compost is dry. Cease feeding
• In cool conditions plants will overwinter in a semi-dormant condition

Plants can be kept small and bushy with regular pruning and may live for up to 20 years.

• Shorten the previous season’s growth in February or early March to leave a framework from which new flower-bearing shoots will develop. Stronger growth can be reduced to 4-7 cm (2-3in) from the base
• Remove thin unproductive shoots and prevent overcrowding
• Trim the tips of young plants to encourage bushiness

Softwood tip cuttings or semi-ripe cuttings taken in late spring or early summer, root readily;

• Dip 7-10cm (3-4in) long cuttings in rooting hormone and insert into trays or pots of sandy cutting compost
• Ideally use a heated propagator, although placing pots within plastic bags in warm windowsills can be effective
• Provide bottom heat of 24-27ºC (75-80ºF) and high humidity to encourage rooting in about two weeks
• Pot rooted cuttings in 9cm (3½in) pots and leave undisturbed over winter

Unfortunately houseplants are not reliably listed in the RHS Plant Finder, as stocks offered in garden centres tend to be sourced abroad making it difficult to identify availablity. Also the range of available Hibiscus rosa-sinensis cultivars is continually changing with new introductions, so it is difficult to make recommendations.

For a variegated form, consider Hibiscus rosa-sinensis ‘Cooperi’ (v) AGM, a compact plant with heavily marbled olive-green and white leaves, sometimes tinted pink and bearing red flowers, height 1-2m (3-6ft)

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Generally trouble free but may suffer from common glasshouse pests such as aphids, red spider mites and glasshouse whitefly.

Flower buds and leaves turn yellow and drop in winter when light levels are low indoors but plants can survive in this semi-dormant state if watering is reduced.