Days are getting shorter and temperatures are dropping; these are hallmarks of the end of summer, but also an indicator you need to change your indoor plant care habits. Plants can sense the different conditions and develop different needs during this time.
Plants enter a kind of dormant phase in the winter and use less energy, which means they also need less water. It’s much easier to overwater a plant during this time than normally. As always the best way to check if a plant needs water is to poke your finger down a couple of inches into the soil – if it’s still moist, hold off on watering.
Here in California most of us are blessed with mild winter temperatures, but if you live somewhere colder you should be careful not to let plants get too cold or they’ll get a kind of frostbite. Indoor plants generally come from tropical regions so they prefer temperatures between 65 and 75 degrees F. Make sure the leaves of plants aren’t touching a window that gets too cold. And note that if you turn up the heat in your place, it’ll dry out the air, so this will affect how quickly the plant’s soil dries out. As always, avoid drafts and air vents.
Fewer hours of daylight and darker, cloudier days may make your plants sad. The best way to make sure they’re still getting enough light is to move them closer to a window (preferably south or east-facing if you’re in the Northern Hemisphere). You should also clean the leaves of any dust or grease to make sure they can absorb as much light as they’re getting, and in extreme cases consider using an artificial light source.
Plants always appreciate nutrients, but because their systems are slower during the colder months and are not in an active growing mode, go much lighter on the fertilization.
Of course these are all generalizations, and different plants have all sorts of different needs. The conditions in your place may also differ in terms of humidity, light, and temperature and these are all things you should take into consideration.