Grow Lights for Bathrooms

We have not tested any of these fixtures. What follows is the manufacturers’ published specifications, our own arithmetic, and one specification that matters more in this room than anywhere else in the house.

A windowless bathroom is where a lot of houseplants go to die slowly, and it is also where people most want one. The humidity genuinely suits tropical foliage. The light almost never does. The fix is a grow light — but a bathroom is a damp location in the electrical sense, and that narrows the field far more sharply than any photon figure.

The specification that decides this page

Lighting products carry a location rating: dry for ordinary interior use, damp for places with humidity and condensation but no direct water, and wet for places where water may contact the fixture directly. A bathroom is at minimum a damp location, and the area in or near a shower is treated as wet.

Here is the uncomfortable finding. Of the seventeen fixtures this site covers, most never publish a location rating at all.

That is not a claim that the unrated products are unsafe. It is a statement about what the manufacturers documented. In a dry living room the distinction rarely matters. In a room that fogs up twice a day it is the first thing to check, and “the manufacturer did not say” is a reason to choose something else rather than to assume.

How much light a bathroom plant actually needs

The plants that suit a bathroom — pothos, philodendron, ferns, calathea, a ZZ plant — are low-light foliage species. Iowa State University Extension puts that group at 3 to 6 mol/m²/day, which is the lowest target on this site.

Twelve micromoles per second is one small bulb. You are not buying a panel for a bathroom, and you should be suspicious of any recommendation that sends you toward one: a high-output fixture in a small tiled room is glare, heat and wasted electricity, aimed at plants that evolved on a forest floor.

1. Feit Electric 16W PAR38 — the only wet-rated pick

Rated for wet locations and for enclosed fixtures, which is the combination you want if the plant lives near the shower or the light goes into a closed ceiling fitting. It publishes 20.0 µmol/s and a 40-degree beam angle, so unlike almost everything else here you can compute what arrives.

So: mount it two feet above the plant, not one. That is a ceiling fitting or a high shelf, which in a bathroom is usually where the socket is anyway.

The downside: it is the least efficient bulb we cover at 1.25 µmol/J, and you are deliberately using a fraction of its output. You are paying for the rating and the optics. Feit also prints its photon figures with broken units, which we unpick in the Feit Electric review.

2. Feit Electric 9W BR30 — a damp-rated flood for one plant

Damp-rated, enclosed-fixture rated, and a reflector flood with a published 110-degree spread, which is a good match for a single plant on a shelf or a vanity a foot or two below. At 9 W it is the cheapest thing here to run, at about $0.59 a month on a 12-hour schedule.

The downside: Feit publishes no photon figure at all for this bulb — it publishes one for its A19 and its PAR38 and nothing for this one — so none of the arithmetic above can be applied to it. You are buying the rating and the shape and finding out the rest after it arrives.

3. GE Grow 48in fixture — a damp-rated shelf run

If the bathroom has a run of shelf or a windowsill ledge with several plants rather than one specimen, the bulb answer stops working and a bar starts. This one is damp-rated, publishes 52 µmol/s from 30 W, and comes with a 5 ft cord and hanging chains.

The downside: it is a 4 ft fixture, so it only makes sense if you genuinely have a 4 ft run. In a small bathroom it will dominate the room visually, and it does not dim.

Glare, mirrors and eye level

One thing is specific to this room. Bathrooms have mirrors, and they have people standing close to fixtures at eye height, often first thing in the morning.

Photobiological safety for lamps is handled by IEC/EN 62471, which sorts sources into risk groups by exposure time and distance. The practical instruction that follows is the same as everywhere else on this site — do not look into the emitters — but a mirror makes that harder to obey by accident. Mount the fixture so the emitter is not in the mirror’s line, or behind the plant rather than in front of it. The fuller treatment is in are grow lights safe for eyes and pets.

Which plants this actually works for

A bathroom grow light does not turn the room into a greenhouse. It moves a dark corner from “nothing survives” to the low band, and that is enough for a specific group.

• Comfortable: pothos, heartleaf philodendron, ZZ plant, snake plant, ferns, calathea. All sit in the 3-6 mol/m²/day band this page targets.
• Possible with the light close: a small monstera, at the top of the band and with slower growth than it would manage in a bright room.
• Not worth attempting: succulents, cacti, herbs, citrus, anything that wants 12 mol/m²/day or more. Delivering that in a bathroom means a fixture far too bright for the room, run long enough to notice on the bill.

The pothos case is the commonest by a distance, and it has its own page with the same arithmetic worked through at plant level: grow lights for pothos.

Running cost, which is the easy part

Under two dollars a month at the top end. Whatever makes this decision for you, it is not the electricity — it is the rating on the box.

Where the fixture goes

A bathroom gives you fewer mounting options than any other room, and the rating you just checked constrains them further.

• An existing ceiling fitting. The cleanest answer if the plant sits below it: a PAR38 in a ceiling can, two feet or more above the leaves, which the distance table above shows lands in the right band. This is also the arrangement furthest from splash.
• A shelf or vanity lamp. A small reflector bulb in a desk lamp beside the plant, aimed down. Keep the cable and the base off the counter surface that gets wet, and out of reach of the sink.
• A bar above a windowsill or a run of shelf. Only worth it for several plants, and only with a damp-rated fixture.

Two habits matter more than the choice: keep the fixture where a shower spray or a splash cannot reach it, and never position it where you would have to reach across it with wet hands. Those are not substitutes for a location rating, and a location rating is not a substitute for them.

Condensation, heat and the fixture itself

A bathroom fogs, and the fog lands on everything including the light. Two consequences are worth planning for.

The first is optical. A film of condensation on a bulb or a lens scatters light, and a fixture that has been rained on by shower steam twice a day accumulates mineral deposits as that water dries. Neither is dangerous in a damp-rated fixture, but both reduce what reaches the plant, gradually and invisibly. Wiping the lens when you clean the room is worth more than it sounds.

The second is thermal. Most of a bulb’s wattage leaves as heat — a 9 W LED emits roughly 3 W as light and the rest warms its surroundings. In a small, closed, already-humid room that is a modest but real addition, and it is one more reason not to mount a fixture tight against a plant or inside an enclosed fitting that is not rated for it. The general case is in do LED grow lights get hot.

The cheaper answer: move the plant

This site sells nothing by telling you not to buy, so it is worth saying plainly. A great many bathroom plant problems are solved by moving the plant to a bright room for a month and rotating it back, which costs nothing.

That works because the low-light species that suit a bathroom are tolerant of variation rather than dependent on constancy. A pothos that spends alternate months on a bright landing and in a windowless shower room does noticeably better than one that spends every month in the dark, and no fixture, rating or cable is involved.

A grow light earns its place when rotation is impractical — there is nowhere bright to rotate to, the plant is large or mounted, or you want the room to look furnished rather than to serve as a plant hospital. Those are good reasons. “The plant is struggling and a light seems like the fix” is a weaker one, and worth testing with a fortnight somewhere brighter before spending anything.

If the bathroom has a window

A bathroom with even a small frosted window is a different problem from a windowless one, and it is worth working out which you have before buying anything.

Frosted or reeded glass diffuses light rather than blocking it, so a frosted bathroom window still delivers usable light to a plant on the sill — often enough for a pothos or a ZZ plant on its own for most of the year. What it does not do is deliver it in winter, at northern latitudes, on a north-facing wall, which is where the fixture earns its place.

For a windowed bathroom, that argues for treating the light as seasonal: run it from October to March, on the same short-day schedule the rest of this site uses for winter supplementing, and switch it off in spring. A plug-in timer makes that a twice-yearly decision rather than a daily one, and the running cost halves.

It also argues for the cheapest pick rather than the best one. A supplement closing a seasonal gap has an easier job than a sole light source, and the 9 W bulb that would be marginal year-round is comfortable for six months alongside a window.