Plants for a Windowless Bathroom
A bathroom seems like a natural home for plants. It is warm, the air is humid, and a bit of greenery makes a small, hard-surfaced room feel calmer. So we are often asked what will grow in a bathroom with no window at all. The honest answer starts with a caveat, and it is one the internet tends to skip.
No plant grows in the dark
Plants make their food from light. A windowless bathroom with the light switched off for most of the day is dark for most of the day, and no houseplant, however tough, can live on a few minutes of light during a morning shower. Lists of plants that "grow in the dark" really mean plants that tolerate very dim light, which is a different thing.
That does not mean a windowless bathroom is hopeless. It means the light has to come from somewhere else.
Making it work
There are three ways to give a plant enough light without a window.
- A grow light. A small LED grow light on a timer, set to run for ten to twelve hours a day, can keep plants healthy in a room with no daylight at all. Modern full-spectrum bulbs give an ordinary white light, so they do not turn the room purple.
- Bright ceiling lights left on for long hours. In a shared office bathroom, or anywhere the lights stay on most of the day, tough plants can get by on artificial light alone, as long as they sit close to the fitting.
- A rotation. Keep two plants and swap them every week or two between the bathroom and a bright room elsewhere, so each gets time to recover.
Our guide to light for houseplants explains how to judge whether a spot has enough, using nothing more than your hand and a sheet of paper.
The plants that cope best
With one of those setups in place, choose plants that tolerate low light and are not fussy about anything else.
Snake plant
A snake plant is the most reliable choice for a dim bathroom. It needs very little light to stay healthy, it does not mind the humidity, and its upright shape suits the narrow spaces bathrooms tend to have, such as the corner beside the toilet or the end of a vanity. Water it sparingly; in a cool, dim room it may need a drink only once a month.
ZZ plant
A ZZ plant is the other strong contender, and it copes with even less light. Its glossy leaves look good against tiles and reflect what light there is. It grows wide rather than tall, so it suits a shelf, a deep ledge or the floor. Its rhizomes store water, so it needs very little.
If you are torn between the two, choose by the space: tall and narrow, or wide and full. Both are toxic to cats and dogs, so keep them out of reach of pets and call your vet if either gets chewed.
For homes with pets
A parlor palm is the best pet-safe option for a dim bathroom. It tolerates low light better than most palms, enjoys the humidity, and is listed as non-toxic to cats and dogs.
What does not work without real light
Ferns are often recommended for bathrooms because they love humidity, and they do. But a fern needs bright, indirect light as well as moist air, and in a windowless room under a ceiling light it slowly turns brown and sheds. If your bathroom has even a small frosted window, a Boston fern hung near it is one of the best bathroom plants there is. Without a window, save it for a brighter room.
The same goes for orchids, calatheas and most flowering plants. They enjoy the humidity but need more light than a windowless room can give without a strong grow light.
Practical tips
- Water less than you would elsewhere. In a dim, humid room the soil dries slowly, and the main risk is rot, not thirst.
- Keep plants away from where they will be splashed with soap or cleaning sprays.
- Dust the leaves now and then. In limited light, every bit counts.
- Watch for slow decline. If a plant is getting paler, stretching or dropping leaves after a few months, it needs more light, and it is time for a grow light or a rotation.
Get the light right, and a windowless bathroom can hold a healthy plant or two for years. Skip it, and even the toughest plant is only borrowing time.