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The Most Important Factor

Understanding Plant Light Needs

Sunlight plays a major role when it comes to keeping indoor plants thriving. Yet how do we truly understand terms like “bright indirect light”? Think about it - light strength varies, windows face different ways, and not every leaf friend likes the same exposure. Work through each section here and start seeing how placement, direction, and plant choice connect.

Indoor Light Levels Explained

Light intensity is measured in foot-candles. Here is what each level means and which plants thrive there.

Bright Direct Light

1,000+ foot-candles

Direct sunlight for several hours a day. Typically found near unobstructed south- or west-facing windows.

Best For

Cacti, succulents, citrus, herbs (basil, rosemary), Fiddle Leaf Fig, Bird of Paradise.

What to Watch For

Plants that need this light will become leggy, pale, or stop flowering if they do not get it.

Bright Indirect Light

500-1,000 foot-candles

Bright light without direct sun hitting the leaves. Found a few feet from south-facing windows, near east-facing windows, or behind sheer curtains.

Best For

Monstera, Pothos, most tropical foliage plants, Fiddle Leaf Fig, Calathea, Philodendron.

What to Watch For

Most popular houseplants thrive here. This is the sweet spot for the majority of indoor plants.

Medium Indirect Light

200-500 foot-candles

Moderate ambient light with no direct sun. Found in rooms with windows where plants sit several feet away, near north-facing windows, or in well-lit rooms with indirect exposure.

Best For

Peace Lily, Dracaena, Chinese Evergreen, some Philodendron varieties, Prayer Plants.

What to Watch For

Plants may grow more slowly than in brighter conditions but remain healthy.

Low Light

50-200 foot-candles

Minimal natural light. Found in interior rooms far from windows, north-facing spaces, dim hallways, and areas lit only by artificial lighting.

Best For

Snake Plant, ZZ Plant, Pothos (solid green), Cast Iron Plant, Peace Lily (less blooming).

What to Watch For

Growth slows significantly. Variegated plants may revert to solid green. Flowering is unlikely.

Light by Window Direction

The direction your window faces determines the type and intensity of light your plants receive. (These guidelines apply to the Northern Hemisphere.)

South-Facing
Brightest. Direct sun for most of the day. Best for sun-loving plants, cacti, and succulents. Filter with sheer curtains for tropical plants.
East-Facing
Gentle morning sun followed by bright indirect light. Ideal for most tropical houseplants that like bright indirect conditions.
West-Facing
Stronger afternoon sun that can be intense in summer. Good for plants that tolerate some direct light. May need filtering.
North-Facing
Least amount of light. No direct sun, only ambient light. Best for low-light tolerant species like Snake Plant and ZZ Plant.

Signs Your Plant Needs Different Light

Needs More Light

  • Leggy, stretched growth reaching toward the light
  • Small, pale new leaves
  • Variegation fading to solid green
  • No flowers on a normally blooming species
  • Very slow or no growth during the growing season
  • Lower leaves dropping off prematurely

Getting Too Much Light

  • Bleached, faded, or washed-out leaf color
  • Brown, crispy patches on leaves (sunburn)
  • Leaves curling or turning away from the light source
  • Soil drying out extremely quickly
  • Wilting despite adequate water
  • Leaf edges turning brown and papery

Using Grow Lights

When natural light is insufficient, LED grow lights can supplement or even replace sunlight for indoor plants.

  • Choose full-spectrum LED grow lights that provide both blue and red wavelengths.
  • Position lights 12-24 inches above the plant canopy depending on light intensity.
  • Run grow lights for 12-16 hours daily to simulate a full growing day.
  • Use a timer so you do not forget to turn lights on and off consistently.
  • Grow lights work well for low-light plants in windowless rooms and for boosting growth in winter.