Put an Ocean spider plant right against a south window, in a 22 °C room at 50% humidity, and it scores 67 out of 100. The sill’s estimated 13,000 lux is a bit more light than this plant wants. One metre back the score is 99, and it stays at 99 or 100 until about four metres into the room.
Read on 14 October 2026, the top results split on whether this window is a problem at all. A-Z Animals calls south windows “bad news” for spider plants, and Joy Us Garden says one will sunburn in the window but do fine near it. Country Living says they do fine there out of direct sun, and a 2021 r/houseplants reply calls the sill fine for a small plant. The careful sources disagree on distance too: the New York Botanical Garden’s library guide asks for “a slightly greater distance” from the sill, and Plant Addicts says several feet back.
Every one of them is arguing about the sill. Scored, the sill is a mild problem, and the fix is about a metre of floor.
Worth a try
It can work here with a little care.
A bit bright, but workable
Comfortable temperature
Humidity suits it
Airflow suits it
Is a south window too much sun for a spider plant?
Only near the glass. On the sill, the card above reads the light as a bit bright, but workable, while warmth, humidity and airflow all sit in their bands. That lands the whole spot at 67, in the worth-a-try band, which the app sums up as a spot that can work with a little care. A spider plant on that sill will get by. It just won’t be doing as well as it would a short walk away.
Half a metre in barely helps. The estimate there is 12,599 lux, still past the top of this plant’s range, and the score moves one point, to 68. That row matters for the advice above, because half a metre is what most people would picture when a guide says slightly further from the sill.
None of the published light figures for this plant mention a window, never mind a distance from one. Here they are as each source prints them:
| Who publishes it | What it says a spider plant needs | What the figure is |
|---|---|---|
| growlightmeter.com | 5 – 10 PPFD / DLI | Spider Plant |
| extension.arizona.edu | 75–150 foot-candles | listed under the heading "Medium Light (75–150 fc)" |
| houseplantjournal.com | 200 FC (40 µmol) foot-candles | minimum indirect light level |
| houseplantjournal.com | 400 FC (80 µmol) foot-candles | good indirect light level |
| houseplantsnook.com | 100–200 foot-candles | chart fc level |
The figures leave the window out, so the search results are what most people go on, and two of them sit closer to the scores than they first look. Joy Us Garden’s version, sunburn in the window but fine near it, lines up with the table if near means a metre. The r/houseplants reply was to someone whose south window gets two to four hours of sun. That’s a dimmer window than the one scored here, and dimming a south sill moves it toward this plant’s band, so for that poster the sill may well have been fine.
Hanging it doesn’t get around the sill. Spider plants often go in a basket hooked into the window frame, and our estimate goes by distance from the glass, so a basket in the opening scores as the sill does. A ceiling hook a metre into the room puts it on the 99 row instead.
How far back from a south window should a spider plant go?
About a metre, and after that there’s more than three metres of floor where the verdict doesn’t change. Here’s one plant moved back from the same south glass:
| Distance from the glass | Estimated light | What the light is doing | Verdict |
|---|---|---|---|
| 0.3 m, against the glass | 13,000 lux | A bit bright, but workable | Worth a try, 67/100 |
| 0.5 m back | 12,599 lux | A bit bright, but workable | Worth a try, 68/100 |
| 1 m back | 10,000 lux | Just the right amount of light | Great fit, 99/100 |
| 2 m back | 6,300 lux | Just the right amount of light | Great fit, 100/100 |
| 3 m back | 3,969 lux | Just the right amount of light | Great fit, 100/100 |
| 4 m back | 2,500 lux | Just the right amount of light | Great fit, 99/100 |
| 5 m back | 1,575 lux | A little dim, but workable | Worth a try, 67/100 |
The step comes between the half-metre and one-metre rows, where the light falls from 12,599 to 10,000 lux and the score jumps from 68 to 99. Scored in finer steps, it lands between 85 and 90 centimetres, just short of three feet. So Plant Addicts’ several feet is the safer reading of the two careful answers, and “slightly” only works if it means a full metre.
Then the table goes flat. Two and three metres both read 100, and four metres still reads 99 at 2,500 lux. Between four and five metres the light runs short instead: five metres back it’s 1,575 lux and 67, a little dim this time rather than a bit bright.
Every lux figure here is an estimate from the window’s direction, the pot’s distance and a clear day, not a meter reading. Your room will move the numbers, but the shape should carry over: a short flagged strip at the glass and a long flat run behind it.
Which window gives a spider plant the most room?
A south one, and the back of the room is where it shows. Same plant, four metres from the glass, with the window turned to face each way in turn:
| The window it is four metres from | Estimated light | What the light is doing | Verdict |
|---|---|---|---|
| North window | 700 lux | A little dim, but workable | Worth a try, 63/100 |
| East window | 1,250 lux | A little dim, but workable | Worth a try, 65/100 |
| West window | 1,500 lux | A little dim, but workable | Worth a try, 66/100 |
| South window | 2,500 lux | Just the right amount of light | Great fit, 99/100 |
At four metres a north, east or west window leaves it short of light, at 700, 1,250 and 1,500 lux, with scores from 63 to 66. The south room still gives it 2,500 lux and 99. For this plant the “bad news” verdict points at the wrong window: south is where it has the most good floor, and the sill is the one part of that floor that costs points.
The other windows keep it closer in. A north window holds a spider plant to about a metre and a half before the light thins out.
A phone can find the great-fit run in your own room. The app’s meter calls anything from 2,500 lux to just under 10,000 bright, indirect, and at this window those two numbers sit on the four-metre and one-metre rows. A reading with that label puts a spider plant inside its great-fit stretch, provided the room isn’t hot.
Does summer heat change the answer?
It changes what stepping back can fix. This plant’s comfortable warmth runs out at about 27 °C. At that point the spot a metre from the glass slips to worth a try along with the sill, for warmth alone, while its light is still right. Moving the pot further back only helps if the back of the room is cooler. The west window page follows that heat ceiling through a hot afternoon.
What should go on the south sill instead?
A-Z Animals’ fallback holds up: put a succulent there. A jade plant does better on a south sill than on any other sill in the house. The spider plant, on a stand a metre in or a shelf across the room, scores higher than it would on the glass.
All of this assumes clear, unshaded glass. An overhang or the building opposite takes light off every row and pulls both edges toward the window, and so does a sheer curtain, which our estimate has no input for. The south window guide sorts the plants that want the full beam from those that need it filtered, and the free spot checker scores your own window with live weather.
Published October 14, 2026
