Plant Light 101
A simple guide to understanding the light you have, and how to make it work for you!
Check Your Light
1. The Shadow Test
Hold your hand 8–12 inches above the plant spot at the brightest part of the day. A sharp shadow usually means direct or very bright light. A soft shadow usually means bright indirect. Almost no shadow usually means low light.
2. The Leaf Test
If the leaves feel warm or hot in the sun, that is direct sun. Many tropical plants prefer the brightness near that area, but not the hot beam directly on the leaves.
3. The Distance Test
Light drops quickly as you move away from a window. A plant directly on a windowsill may receive many times more light than one across the room.
4. The Lux App Test
A lux meter app or handheld light meter can help. Use the number as a guide, not a perfect science. Measure where the leaves actually sit, not at the glass.
Light & Warning Signs
Too Little Light
Leggy growth, leaning toward the window, smaller leaves, fading variegation, slow drying soil, little new growth.
Too Much Light
Bleached leaves, crispy brown patches, curled leaves, hot leaves, faded color, scorched edges.
☀️ Bright Direct Sun
Direct sun means the sun’s rays physically touch the plant leaves. You will usually see a clear beam of light, strong shadows, and warmth on the leaves or pot.
- How to tell: Your hand casts a sharp, dark shadow.
- Common spots: Unshaded south or southwest windows.
- Approx range: Over 1,000 foot-candles / about 10,700+ lux.
- Good for: Cactus, succulents, jade, citrus, croton, some palms.
- Watch for: Bleached, crispy, or brown leaf patches.
🌤 Bright Indirect Light
Bright indirect light is strong daylight without harsh sun rays directly hitting the leaves. This is the favorite range for many tropical houseplants.
- How to tell: The room is bright, but shadows are softer.
- Common spots: Near east/west windows, or pulled back from south windows.
- Approx range: About 500–1,000 foot-candles / 5,400–10,700 lux.
- Good for: Monstera, pothos, philodendron, hoya, anthurium, syngonium.
- Watch for: If leaves are hot to the touch, it may be direct sun.
🌥 Medium Indirect Light
Medium light is usable daylight, usually near a window but without direct sun. Many easy-care plants tolerate this well, though growth may be slower than in brighter light.
- How to tell: You can read comfortably without turning on a lamp.
- Common spots: North windows, shaded east/west windows, a few feet from glass.
- Approx range: About 100–500 foot-candles / 1,000–5,400 lux.
- Good for: Pothos, philodendron, dracaena, Chinese evergreen, ferns.
- Watch for: Long spacing between leaves means the plant wants more light.
🌑 Low Light
Low light does not mean no light. It means very limited natural light, often far from a window or in a heavily shaded room.
- How to tell: Shadows are faint or nearly gone.
- Common spots: Far from windows, north rooms, offices with overhead lighting.
- Approx range: About 25–100 foot-candles / 270–1,000 lux.
- Good for: ZZ plant, snake plant, cast iron plant, pothos, peace lily.
- Watch for: Leggy growth, leaning, fading color, and slow growth.
🌘 Very Low Light
Very low light is a spot with barely usable natural light. Some plants may tolerate it for a while, but growth will usually be very slow and the plant may gradually decline without help.
- How to tell: The area feels dim even during the day, and shadows are almost gone.
- Common spots: Interior corners, hallways, bathrooms with tiny windows, or rooms far from glass.
- Approx range: Under 25 foot-candles / under 270 lux.
- Good for: Short-term display only, or use with a grow light.
- Watch for: Yellowing, leaf drop, stretching, wet soil staying wet too long, and stalled growth.