Houseplant hacks: Are windowsills too cold for plants in winter?

The problem
That bright window spot you chose for your houseplants to receive maximum sunlight can become one of the coldest places in the house in winter. The glass itself can get cold, and with heavy curtains drawn, it creates a cooler box area around your window. For tropical plants like anthuriums and philodendrons, which are used to less temperature fluctuation, the cold can be fatal.

The hack
Move sensitive plants back from the glass overnight, then return them to their brighter position in the morning.

The method
Start by using a thermometer to check how cold the windowsill actually gets. If you don’t have heavy curtains, keep leaves from touching the glass; if you do, move the plants from the windowsill into the room overnight.

The test
During winter, I left some plants on a south-facing windowsill and moved others into the room. (For context, I live in a centrally heated home with double-glazed windows.) In rooms where I don’t use the heating, the windowsill temperature dropped to around 15C overnight. My more delicate tropicals were happier away from the cold windowsill, while hardier cacti were happy to stay put. I also saw less leaf damage by not letting foliage touch the cold glass.

The verdict
If you have draughty glazing and tropical plants, it is worth the shuffle. Sometimes good winter care really is as simple as moving a pot.