How to help your houseplants through the Winter.
Here in the UK, the next five or six months represent quite a challenge for the indoor gardener, as plants struggle with an unwelcome combination of shorter days and lower light levels, dry air, daytime heat and evening chill. But a few tips can go a long way towards alleviating some of the problems our houseplants face at this time of year.
October to March is the resting phase for most houseplants and we must adjust our habits accordingly or we add to their difficulties. The most important change to make is with our watering regimen. Plants that are not actively growing don't require regular watering - depending on the species you may want to cease watering altogether - or else water only very infrequently when the soil has almost entirely dried out. Don't let a plant sit in water. This is never more important than during Winter months, when prolonged wet and cold soil will lead directly to root rot. Feel down into the soil a couple of centimetres and if it's dry, give it a small drink with tepid water. It's always good practice to use tepid or at least room temperature water to avoid shocking a plants root system - but again it's never more important to do so than now. (Plant Lady Sophie is dedicating an entire blog post to correct watering in the upcoming weeks, so watch this space, as some expert watering advice is coming your way!)
There's no need to feed a resting plant, so you can stop fertilising until around March or when you start to see signs of fresh, green growth. Remember, Winter is not a time to repot or to take cuttings. Let your plants rest properly and save those jobs for Spring, when the new season of active growth begins.
It's a good idea to bring your houseplants right up to the windows over the next few weeks so that they can make the most of the shorter daylight hours. (But be wary of frosty windowpanes or places where they might receive a draft.) South or West facing windows receive the best (and longest) light, or you might want to invest in some supplemental lighting. Florescent lights are cheaper than grow-lights, and whilst they don't provide a full spectrum for optimum growth, they can be an adequate 'top-up'. Cleaning your windows and wiping dusty leaves will also help your plant to do the best it can with the light available.
Avoid placing your plants near cold drafts or heat sources and remember that most plants will be unhappy with large temperature fluctuations. In Winter, the humidity levels in our homes can drop to as low as 10 to 20% due to our near constant use of central heating. Plants prefer around 50%, so if you don't have a humidifier, you'll have to cluster your plants together, relocate them to a bathroom or use that old pebble tray trick to raise the humidity back to levels they're comfortable with.