A peace lily on a north sill, at 22 °C and 50% humidity, scores 99 out of 100. Carry it four metres from the glass, at roughly London’s latitude, and it still scores 98 in June. Only in November, December and January, with the estimate down near 350 lux, does that far spot slip to 68. On the sill itself, the score follows the thermometer.
Read on 14 October 2026, the pages ranking for this search mostly like a north window for a peace lily and then hedge, on flowers and on distance. An extension service and a plant shop name north as a top spot, and a grow-light maker says it flowers even in shaded north windows. A Tom’s Guide piece on Yahoo says north will do “in a pinch” and may fall short for flowers. On distance the hedges stay tight: within a metre, preferably on the sill, says Gardeners’ World; under a foot from the glass, says a 2022 r/plants reply, or a grow light in the corner.
Both hedges are about light. For a peace lily in a north window, light turns out to be the forgiving part.
Great fit
This plant should be happy in this spot.
Just the right amount of light
Comfortable temperature
Humidity suits it
Airflow suits it
Is a north window bright enough for a peace lily?
Plenty bright. The card puts a north sill inside this plant’s light band, with the other three readings in band as well, which is how it reaches 99. The peace lily light page lays the band out in lux and scores two spots further inside a north window; both stay in it.
Other windows ask more of the room. In a west room it needs about two metres of clearance before its light stops being flagged, and a south room pushes that to three. A monstera at this same north window is down to worth a try by two metres, because the dim end of its range sits higher.
Six published light figures for a peace lily, from five sources in three units, and none of them tied to a window direction:
| Who publishes it | What it says a peace lily needs | What the figure is |
|---|---|---|
| theplantrunner.com | 800–2,000+ lux | Standard foliage plants (pothos, Philodendron, Monstera deliciosa …) — a general band, not a single-species figure |
| houseplantjournal.com | 100 foot-candles | Peace Lily — minimum indirect light |
| houseplantjournal.com | 200 foot-candles | Peace Lily — good indirect light |
| growlightmeter.com | 5 – 10 PPFD / DLI | Peace Lily |
| extension.arizona.edu | 75–150 foot-candles | listed under the heading "Medium Light (75–150 fc)" |
| houseplantsnook.com | 50–100 foot-candles | chart fc level |
The flowering half of the argument is one our score can’t referee: the engine rates how well a spot suits the plant, with no model of blooming, so the 99 says nothing about flowers.
How far into a north room can a peace lily go?
Well past a metre. Gardeners’ World pairs its one-metre advice with a warning that root rot is likelier further from the window; our score has no model of watering, so that half stays untested. The light half doesn’t need the metre. On a plain clear day the score barely moves between the sill and six metres back, so a distance table would print one verdict six times. The calendar is what finds the edge.
The lux in the next table is an estimate: window direction, distance, date and a clear sky go in, and no meter is involved. A balcony overhead or a narrow window will pull the far spot under the band sooner than this. This is a pot four metres back, at latitude 51 degrees, from midsummer round to February:
| The month it is | Estimated light | What the light is doing | Verdict |
|---|---|---|---|
| June | 840 lux | Just the right amount of light | Great fit, 98/100 |
| October | 509 lux | Just the right amount of light | Great fit, 97/100 |
| November | 354 lux | A little dim, but workable | Worth a try, 68/100 |
| December | 350 lux | A little dim, but workable | Worth a try, 68/100 |
| January | 360 lux | A little dim, but workable | Worth a try, 68/100 |
| February | 518 lux | Just the right amount of light | Great fit, 98/100 |
June and October both sit inside the band at that spot. November takes the reading from 509 down to 354 lux, the light column switches to a little dim, and the verdict to worth a try at 68, where it stays until February lifts it back to 518 lux. Further south the winter sun climbs higher: at New York’s latitude the same spot holds a great fit right through the winter.
Nearer the glass, we ran every month at this latitude from half a metre to three and a half metres back, and none of them dropped out of great fit. The sill itself drifts just over the top of the band around midsummer; the winter guide scores a peace lily on a north sill month by month, and there the month that loses points is June. So the two tight answers above are safe. They just leave most of a north room empty.
What a north window doesn’t change is the air. Every table on this page holds humidity at 50%, the bottom of the range the care data asks for, and a heated room in January often sits lower. The west-window page walks humidity down at a spot whose light is already right; read it once the heating comes on.
Air movement is held at light, the setting the care data asks for. Run the same tables at medium and every row gives up a few points, but not one verdict changes.
Can a north windowsill get too cold for a peace lily?
Yes, and on the sill that outweighs anything the light does. Nothing but room air warms a north pane in winter, and after dark the thin layer of air touching it can be the coldest in the room. Here is the sill from the card with only the air temperature changing:
| Air temperature at the sill | What the light is doing | Verdict |
|---|---|---|
| 13 °C | Just the right amount of light | Not the best fit right now, 44/100 |
| 15 °C | Just the right amount of light | Not the best fit right now, 47/100 |
| 16 °C | Just the right amount of light | Worth a try, 63/100 |
| 18 °C | Just the right amount of light | Worth a try, 67/100 |
| 19 °C | Just the right amount of light | Great fit, 97/100 |
| 21 °C | Just the right amount of light | Great fit, 99/100 |
Every row has its light right, and the verdict still falls: 99 at 21 °C and 97 at 19, then a drop to 67 at 18 °C, 63 at 16 and 47 at 15. The care data we score against lists 16 °C as this plant’s minimum, which is why 16 still reads worth a try and 15 does not. A sill at 15 °C scores lower than the far wall does in December.
Leave a thermometer by the pot for one cold night; its lowest reading is your row. Under 19 °C, move it a metre back, where the air is usually warmer and the light still holds all year.
Where should a peace lily go in a north room?
From just off the glass to three and a half metres back, in a room kept at 19 °C or warmer. Net curtains or a building close opposite take light off first, and the score sees neither. The north window guide has what else holds in this light. The free spot checker will run your own window with the weather where you are.
Published October 14, 2026
