Looking after houseplants through the winter
Short days and central heating change conditions indoors more than most people notice. Houseplants slow down in winter, and a few small changes to where they stand and how you care for them will carry them through to spring.
Move plants towards the light
Winter light is weaker and the days are short, so move plants closer to the windows or into a brighter room. A plant that was happy a few metres back from the glass in summer may need to be right beside it now. Clean the windows on the inside, as a dirty pane cuts out more light than you might think. On cold nights, don't leave plants trapped between drawn curtains and the glass, where the air can get close to freezing.
Water and feed less
Growth slows right down in low light, so most plants need watering much less often than in summer. Cacti and most succulents need little or no water until spring. Lift each pot before you water it: one that still feels heavy has plenty of moisture left. Stop feeding from mid autumn until new growth appears in spring, as plants can't use the extra food.
Warmth, draughts and dry air
Most houseplants are happiest between about 15 and 21°C. Keep them away from radiators and heaters, which dry out the leaves, and out of cold draughts from doors that open often. Central heating makes the air dry, which can cause brown leaf tips. Grouping plants together helps, as does standing pots on a tray of damp pebbles with the base of each pot above the water.
Once a week we walk round the house and look closely at every plant, checking the compost, the undersides of the leaves and any new growth. We think of it as the pereparur tour, and it means problems such as pests or rot are spotted while they are still small and easy to deal with.
Pests that like warm, dry rooms
Spider mites and mealybugs thrive in heated rooms. Fine webbing, pale speckles on the leaves or small white fluffy patches where the leaves join the stem are the signs to look for. Move an affected plant away from the others, wipe the leaves with a damp cloth or rinse the plant in the shower with lukewarm water, and keep checking it for a few weeks.