How To Tell If Houseplants Are Getting Enough Light

Besides deciding when to water, deciding how much light to give a houseplant is the next biggest challenge. Sometimes we don’t have much choice. Maybe we have limited window space or our windows face a certain direction or we’d like a plant on a coffee table instead of in front of the window.

How can we tell if the spot we’ve chosen for a plant is good enough? How do we know if the plant is happy in the location we’ve chosen?

Here’s how to tell if houseplants are getting enough light to keep them healthy and thriving:

  1. Easiest-to-see sign is if the plant becomes “spindly” or “leggy.” The space between leaves becomes greater. Leaves are no longer as closely spaced along the stem. Look at the older growth, and the spacing between leaves. Then look at the newer growth at the plant tips. Are the newer leaves spaced out farther along the stem? This is called the internode area, the area between nodes. Nodes are the raised bumps along the stems from which leaves and growth arises.
  2. If plants are getting enough light for good growth, the new leaves will be spaced closely along the stem, like the older, original growth that’s lower down in the plant. That’s the growth that occurred under ideal conditions in the greenhouse in which the plant was produced.
  3. If it’s the type of plant that doesn’t have leaves spaced along a stem, but instead rises from a central crown, such as ferns or peace lily, observe whether new shoots are being produced. New healthy shoots arising every so often from the plant’s center is a good sign.
  4. New leaves that are smaller than older leaves, even when fully expanded indicate lower-than-optimal light.
  5. If it’s a variegated (two-tone) leafed plant, new leaves sometime lose the variegation and expand to be all-green if light levels are lower than preferred.
  6. New leaves may be thinner in texture under low light.
  7. Besides observing new growth, check older leaves. Under less-than-ideal light, older leaves will sometimes become yellow and drop. This can also be coupled by watering problems, which often go hand-in-hand with low-light levels.

What to do if a houseplant is showing light-deprivation symptoms? Increase light by moving the plant closer to window. Open drapes wider. Tie back sheer-type curtains, if used. Choose a plant type with lower light requirements. Dusty leaves reduce a plant’s ability to use light – wipe leaves gently with soft cloth.

Happy Gardening!