Although most of us have heard that human beings aren’t so great at seeing in the dark, we’re actually not that bad at it. Not as good as cats and other nocturnal animals, perhaps, but compared to most diurnal animals, we see pretty well in partial obscurity. And that can cause problems for our houseplants.
Since our eyes adjust so well to low light, we’re really very poor at judging light levels. For example, we tend to see most indoor situations as brightly lit while they often receive very little light. And that makes us horrible at choosing places to put houseplants.
Plants Depend on Light
Plants need light to survive. They get all their energy from sunlight (unless we supply artificial light, of course) and if they don’t get enough, they either stop growing or etiolate (stretch for the light). Eventually, they die! Yet we can’t trust our eyes when it comes to placing them.
The Newspaper Test
That is, unless you pick up a newspaper or a book with similar size print. On a bright, sunny day, pull up a chair in the spot where you intend to grow the plant and try to read for 10 minutes.
If you find it easy to do, the spot is receiving bright light and most plants will thrive there.
If you find it hard or impossible to do, it receives poor light and only the most shade-tolerant plants will survive there … and even then, probably won’t grow much.
If you can read there, but it’s a bit of a strain, or if you instinctively feel like turning on a lamp, that’s medium light, good enough for some plants, although most would do better with bright light.
It’s best to take the newspaper test several times a year, notably in winter, when light levels indoors are extremely low. A spot that was in bright light in the summer can well be in low light in the winter, for example.
You’ll soon find that, if you want happy houseplants, you’ll have to move most of them to brighter spots for the winter.