Grow Light for Bathroom Plants in Windowless Rooms
A grow light for bathroom plants can stand in for the window a windowless room lacks. University of Missouri Extension notes plants that get little or no natural light need artificial light for adequate growth. Pick plants that like humid air, then run a lamp on a timer for a steady day.
The short answer
In a windowless bathroom the lamp is the only light source. University of Missouri Extension advises 16 to 18 hours a day for plants with no outdoor light. University of Illinois Extension advises no more than 16 hours, since plants need a rest. A timer holds the day steady while humid air suits many foliage plants.
Can plants grow in a windowless bathroom?
Yes, with a lamp. University of Missouri Extension notes plants with little or no natural light need artificial light. University of Maine Cooperative Extension notes grow lights can make a poorly lit corner a good place for plants.
| Plant | Light need | Note |
|---|---|---|
| Aluminum plant | Low light | Needs high humidity |
| Begonias | Medium light | Like high humidity |
| Asparagus fern | Tolerates low light | Grows denser with more |
| Arrowhead vine | Low to medium light | Denser at medium light |
Source: University of Missouri Extension.
How long should a bathroom grow light run?
University of Missouri Extension advises 16 to 18 hours a day for plants that get no outdoor light. University of Illinois Extension notes 14 to 16 hours is sufficient in low light plus advises no more than 16. University of Maine Cooperative Extension advises a simple timer for the light period.
Which grow light suits a bathroom?
University of Maine Cooperative Extension lists fluorescent, LED plus HID lamps, with budget as the main factor. University of Illinois Extension notes cool white fluorescent bulbs work well for foliage plants.
How to: step by step
- Choose plants suited to humid air.
- Choose an LED or fluorescent fixture.
- Mount it above the plants.
- Set a timer for 14 to 16 hours.
- Water only when the soil feels dry.
- Adjust height or hours based on new leaves.
Troubleshooting
Long gaps between leaves: too little light. Lower the lamp or add hours.
Pale leaves: low light. Add hours up to 16.
Lower leaves yellow plus drop: low light. Bring the lamp nearer.
For more on lighting see grow lights for cannabis, grow light timers, optimal lighting for growing indoors plus cannabis seeds. Kind Seed Co also stocks seeds for indoor growers.
Sources
- Lighting indoor houseplants (G6515), University of Missouri Extension
- Lighting, houseplants, Illinois Extension
- Growing houseplants under artificial lights in Maine (Bulletin 2614), University of Maine Cooperative Extension
FAQ
Which plants like a humid bathroom?
University of Missouri Extension notes aluminum plant needs high humidity plus tolerates low light. It notes begonias like high humidity plus constantly moist soil, with 14 to 18 hours of light. Artillery fern plus moon valley pilea are related plants that suit the same conditions.
How do I know a bathroom plant needs more light?
University of Missouri Extension lists long internodes, smaller leaves, pale stems plus foliage plus lower leaves that yellow plus drop as signs of too little light. University of Maine Cooperative Extension adds spindly new growth plus poor blooming. Lower the lamp or add hours when these show.
Can a plant get too many hours of light?
Yes. University of Illinois Extension advises no more than 16 hours of light a day, since plants need a rest period too. University of Missouri Extension notes some plants need up to 18 hours with no outdoor light. Start at 14 to 16 hours plus adjust from what the plants show you.
Does a bathroom ceiling light count?
Rarely enough. University of Missouri Extension notes incandescent lights are a poor single light source because they are low in blue light. University of Illinois Extension notes plants need blue plus red light, so add a grow lamp on a timer.
How often should I water bathroom plants?
University of Maine Cooperative Extension advises caring for plants under lights as you would under natural light plus monitoring water needs closely. University of Missouri Extension notes begonias like constantly moist soil. Feel the soil before each watering plus empty any water left in the saucer.
