Does window direction tell me how much light a room gets?

Direction is the single biggest factor. In the northern hemisphere, south-facing windows get the most total light and the most direct sun. North-facing windows get the least. East windows get cool morning sun; west windows get strong afternoon sun. Beyond direction, light also depends on window size, outdoor obstructions like trees or overhangs, and how far back from the window the plant sits.

How Much Light Do Houseplants Need? A Guide to Indoor Light Levels

Q: How do I know if my plant is getting enough light?

Signs of too little light include: the plant stretches toward the window, new leaves come in smaller than old ones, variegated plants lose their pattern and go plain green, growth slows almost to nothing, and the soil stays wet for a long time after watering because the plant is not actively growing. Signs of too much direct sun include scorched or bleached patches on the leaves, usually where the sun hits first.

Q: Can I use my phone to measure light?

Phone lux meters give rough readings that are useful for comparison rather than precision. Place the phone face-up where the plant will sit, open a lux meter app, and note the reading in full daylight conditions. Under 500 lux is low light. 500 to 2,500 lux is medium to bright indirect. Above 2,500 lux with visible sunbeams is direct sun. Different apps and phone models vary, so treat readings as approximate.

Q: Does light change between seasons?

Significantly. The sun tracks lower across the sky in winter, which means less total light through any window and a shorter photoperiod. A south window in December delivers about half the daily light it does in June. Plants grown in summer may need to move closer to the window in winter, and fast-growing plants slow considerably regardless of care.

Light is the variable that determines whether a plant thrives or slowly declines. Get the light right and most other care decisions become more forgiving. Get it wrong and no amount of careful watering or fertilizing compensates. Here is how to read the terms on plant labels and match them to what your home actually provides.

The four light levels explained

Low light

A spot that gets no direct sun and only soft ambient daylight from a window across the room or from a north-facing window. You can see well enough to read, but the room feels dim. Roughly 25 to 200 foot-candles of illumination. Plants that genuinely tolerate this level are forest-floor plants that evolved under dense canopy: snake plant, ZZ plant, cast iron plant, pothos, and peace lily.

Medium indirect light

Bright enough to read comfortably anywhere in the room, but still no direct sun patches on the floor. Common in rooms with east or west windows, or in the middle of a large south-facing room. Roughly 200 to 500 foot-candles. Calathea, prayer plant, Chinese evergreen, and philodendrons prefer this range.

Bright indirect light

The room is clearly well-lit and you can feel warmth through the window, but direct sunbeams do not hit the plant. A position right beside a large east or west window, or about 60 to 90 cm back from a south window. Roughly 500 to 2,000 foot-candles. This is the most common requirement for popular tropical houseplants: monstera, fiddle leaf fig, rubber plant, hoya, alocasia, and anthurium.

Direct sun

Actual sunlight falls on the plant's leaves for some portion of the day. A south-facing window up close. Full sun outdoors. 2,000 foot-candles or more, up to 10,000 outdoors on a clear day. Succulents, cacti, most herbs, and outdoor vegetables need this level. Many popular houseplants will scorch here.

How window direction maps to light level

Direction is the fastest way to estimate light without any equipment:

South window: direct sun for several hours mid-day, plus bright indirect through the rest of the day. The brightest window in the northern hemisphere.
East window: direct morning sun (usually 2 to 4 hours), then bright indirect through the afternoon. Comfortable for a wide range of plants.
West window: bright indirect in the morning, then direct afternoon sun (often intense in summer). Similar total light to east, but hotter in the afternoon.
North window: low to medium indirect light all day, little to no direct sun. Best for shade-tolerant plants.

Not sure which direction your windows face? The window direction guide has three quick methods.

Distance from the window matters too

Light intensity falls off quickly as you move away from a window. A plant sitting right on the sill gets dramatically more light than one a metre away from the same window. As a rough guide: most houseplants that want bright indirect light need to be within 1 to 1.5 metres of the window. Beyond that, even a large south window reads as low to medium light for the plant.

How to estimate light without equipment

The shadow test: hold your hand about 30 cm above a white piece of paper where the plant will sit, in normal daylight conditions.

Sharp, clearly defined shadow: direct sun
Soft, visible shadow with fuzzy edges: bright indirect
Very faint, barely there shadow: medium indirect
No shadow at all: low light

A phone's lux meter app gives rough numbers if you prefer something measurable. Place the phone face-up where the plant will sit and check the reading in full daylight. Under 500 lux is low light; 500 to 2,500 is indirect; above 2,500 with sunbeams present is direct. Treat readings as approximate since apps and phones vary.

Seasonal light changes

The sun tracks lower in the sky in winter, which means less total daily light through any window and a shorter day. A south window in December can deliver roughly half the light it does in June. Plants that grow vigorously in summer often slow considerably in winter regardless of care. Moving them closer to the window in late autumn and back out in spring helps buffer the change.

Signs the light level is wrong

Too little light: the plant stretches or leans toward the window, new growth comes in smaller than existing leaves, variegated plants fade to plain green, growth stops almost entirely, or the soil stays wet for an unusually long time because the plant is not drinking.

Too much direct sun: pale or bleached patches on the leaves, usually in the spots where the sun hits first. Crispy leaf edges in the afternoon.

Know exactly what each window delivers

Plant Compass Lite uses the real solar path for your location to calculate how many hours of direct sun each window direction gives, across every season. Point at any window and see what light it actually provides.

Get Plant Compass Lite

Frequently asked

How do I know if my plant is getting enough light?

Signs of too little: the plant stretches toward the window, new leaves come in smaller, variegated plants lose their pattern, growth nearly stops, soil stays wet for too long. Signs of too much direct sun: pale or scorched patches on leaves, crispy edges.

Does window direction tell me how much light I have?

It is the biggest single factor, yes. South windows get the most total light and the most direct sun in the northern hemisphere. North windows get the least. Beyond direction, window size, outdoor obstructions, and distance from the window all affect the final light level a plant experiences.

Can I use my phone to measure light?

Roughly, yes. Place the phone face-up where the plant will sit, open a lux meter app, and note the reading in full daylight. Under 500 lux is low light; 500 to 2,500 is indirect; above 2,500 with visible sunbeams is direct. Different apps and phones vary, so treat readings as approximate.

Does light change between seasons?

Significantly. The sun tracks lower in winter, giving less daily light through any window. A south window in December delivers roughly half the light it does in June. Plants that grow fast in summer often slow considerably in winter regardless of how you care for them.

Dig deeper: the best low light plants, the best plants for bright indirect light, or what thrives in a north-facing window.