Advice
RHS Help & Advice
Houseplant care
Choose
houseplants suited to the light levels and temperatures of
your home to avoid disappointment. Most houseplants require
little attention apart from regular watering and feeding and
occasional potting on.
Light
Most plants require bright filtered light. Light levels decrease rapidly as plants are placed further back from the window. Our eyes compensate for this lack of light. Low light levels can lead to a decline in health as insufficient food is produced to replace older leaves as they die, leaving pale stunted plants. Too much light can lead to scorching of the foliage with many tropical houseplants.
Temperature
Although many houseplants require warm rooms, they generally prefer an even temperature. In winter this becomes a problem when central heating creates large fluctuations between day and night temperatures. Avoid placing plants near radiators, in draughts, or on windowsills at night.
Humidity
Many tropical plants require a humid atmosphere. Mist plants daily, or place on a tray of damp gravel. Plants grouped together will create a humid micro-climate around their leaves. Low humidity is a problem in centrally-heated rooms in winter.
Water
Indoor plants more commonly die of over-watering, than from drought. Overwatering eventually leads to root death and collapse of the plant. Keep plants just moist. Avoid letting the compost dry out completely. As the compost dries it becomes lighter in weight and often paler in colour. Water from below allowing the plant to take up water as it is needed, but allow excess to drain away. Brown tips and margins of the leaves often indicate that the compost or atmosphere is too dry. Always use tepid water to prevent temperature shocks to the roots.
Feeding
Liquid feeds are generally the best for houseplants. Choose one high in potash for flowering pot plants, more balanced for foliage plants. Slow-release fertiliser tabs or granules will last the growing season, but may concentrate the nutrients to one side of the pot. Specialist feeds are available for certain groups of plants such as orchids and citrus. Most plants should only be fed when actively growing in March to September; flowering plants should be fed when in bud and flower.
Repotting
After a year or two plants may need repotting into a larger container to maintain healthy growth. Choose a clean pot one or two sizes large than the old one. Water the plant before potting and allow to drain. Repot using a similar type of compost to the old one. Never repot unless the plant actually needs it.