Houseplant care
Make sure houseplants are receiving as much natural light as possible to thrive over winter. They can easily be forgotten in a spare room that receives little natural light, or with the curtains left drawn. They are best moved to a sunny windowsill until March. Don’t leave houseplants on windowsills behind the curtains on frosty nights, especially if your windows are not double glazed.
Water houseplants sparingly. The compost should be barely moist in winter. Putting a finger into the compost can indicate moisture levels at root depth.
From the end of the month, cut back leggy Hypoestes (polka dot plant), Pilea (aluminium plant), Solenostemon (formerly Coleus) and Tradescantia to encourage new growth.
Clivia benefit from a dormant period over winter, with less watering, feeding and lower light levels.
Cool conditions and regular watering will help keep potted indoor azaleas looking good for longer. Remember to water azaleas with rainwater collected in a water butt, not with tap water.
Bulbs and corms
Place hyacinths in a cool, bright place in the home. If it’s too warm, the leaves will elongate and the flowers will fade quickly.
Indoor forced bulbs used for Christmas displays, and which have now finished flowering, can be left outside in a sheltered spot in the garden, to finish dying down. Hyacinths can be planted outside in the garden.
Support tall bulb flower spikes with canes to stop them flopping.
Continue to water Hippeastrum (amaryllis) bulbs after flowering. Boost bulb growth and flowering for next year with an organic houseplant feed.
Cyclamen persicum appreciates a cool room with good light. If leaves on cyclamen start to turn yellow, this may be a sign of overwatering. Once the compost starts to feel dry to the touch, water from below (into the saucer), and allow the plant to drink for up to half an hour before pouring away the excess water left in the saucer – wetting the leaves can easily result in rotting off.
Cacti
Remember that cacti need very little water, and no feeding, over winter. Keep the compost barely moist until the spring, when they may flower and will therefore need more water and feed.
Encourage bushy growth on Christmas cacti (Schlumbergera truncata and S. × buckleyi) by twisting off outer segments from the most vigorous shoots after flowering. These can be used as cuttings if left to one side and kept warm for a week, for the cut surface to callous over, before potting up.
If your Christmas cactus didn’t flower, it may be that the temperature is too high (above 18°C), or that the plant is receiving light from an artificial light source after dark. Try moving the cactus into cooler conditions or away from night lighting.
In the greenhouse
Check that greenhouse heaters are meeting the required temperature, by investing in a maximum-minimum thermometer to enable accurate monitoring of greenhouse temperatures. Tender and half-hardy plants such as Fuchsia and Pelargonium generally need a minimum of 5°C, so you may only need to heat during cold spells.
Check your greenhouse insulation to make sure it is still secure.
Remove snow from greenhouse and conservatory roofs, to prevent damage and allow good light penetration.
Clear leaves and twigs from guttering on greenhouses and sheds.
Ventilating the greenhouse on mild, sunny days will help to reduce fungal infections.
Fuchsias can be started into active growth by re-potting with peat-free compost, increasing watering, feeding with seaweed feed, and putting them in a sunny place.
Problems
Regularly pick over plants and sweep up fallen debris, to prevent disease appearing and spreading.
Look out for cyclamen grey mould. Pick off affected leaves and compost them.
This is a good time to clean all your old pots and seed trays, so that they are ready for spring’s flurry of activity. Thorough cleaning will reduce pest and disease problems. Hot soapy water will clean well, without unpleasant odour or toxicity to plants.
