Indoors, light is the constraint most people underestimate. A plant placed two metres back from a window receives a small fraction of the light it would get on the sill, even though the room looks bright to our eyes. The eye adjusts; a plant cannot. Choosing the right window, and the right distance from it, does more for a houseplant than any feeding routine.
What each window direction gives
Window orientation sets the ceiling on how much light a spot can offer. In the northern hemisphere, the broad pattern is consistent, though the low winter sun shifts the balance through the cold months.
| Window | Typical light | Suits |
|---|---|---|
| South-facing | The brightest exposure; direct sun for much of the day. | High-light plants; sun-lovers, with sheer shielding in summer. |
| East-facing | Gentle direct morning sun, then bright indirect light. | Many foliage plants that like bright but not harsh light. |
| West-facing | Bright indirect light with stronger, warmer afternoon sun. | Plants that tolerate some direct light, set slightly back. |
| North-facing | The dimmest; steady indirect light, no direct sun. | Low-light tolerant plants placed close to the glass. |
The winter dip
From late autumn through early spring, daylight is short and the sun stays low. A south window that was almost too bright in July may become the only spot bright enough in January. It is normal to move plants closer to windows for the winter and back during the long summer days. Slower growth and fewer new leaves in winter are usually a light-and-temperature response, not a problem to fix with extra water or feeding.
Common plants by light tolerance
- Snake plant (Sansevieria): tolerates low light but grows better in bright indirect light. Very forgiving of position.
- Pothos (Epipremnum): does well in moderate to bright indirect light; pale, leggy growth signals too little light.
- ZZ plant (Zamioculcas): tolerant of low and moderate light, which makes it a candidate for interior and north-facing rooms.
Reading the plant
Plants report their light. Long gaps between leaves, stems stretching toward the window, and small pale new growth point to too little light. Scorched, bleached patches on leaves that face direct sun point to too much. Shifting a plant a metre toward or away from the glass, or to a different window, is often the entire fix.
Supplementing with grow lights
Where natural light falls short, especially in winter, an artificial grow light on a timer can help. General guidance for foliage houseplants is in the range of roughly twelve to fourteen hours of supplemental light per day, adjusted to the plant and the room.
Publicly available references
Related