Plant care calculator

Plant Light Calculator: Where Should You Put This Plant?

Determine the ideal indoor light placement for your plant based on species, window direction, and seasonal light availability.

Quick Answer

By factoring in your specific plant type and environmental conditions, you can precisely tailor your care routine to ensure optimal health and prevent common issues like root rot.

Language & Region

Enter your details

Enter your details below to generate a custom recommendation.

Environment

Window / Exposure Direction

Direct Sun Hours

Distance From Window

Enter in Meters for Metric or Feet for US Standard.

Obstruction Level

Units

Unit System

Additional Options

Light Meter Reading (Lux) - Optional

Light Meter Reading (Foot-candles) - Optional

The Problem

Many plant owners guess at their care routines, leading to root rot, burned leaves, or stunted growth. Generic advice doesn't factor in specific plant species and local climate.

When to Use This Tool

Use this calculator when you bring home a new plant, when seasons change, or if your plant is showing signs of distress.

Who is this for?

Beginner houseplant owners looking to avoid common mistakes
Advanced collectors wanting to optimize growth rates

Find the ideal light placement for your plant collection Using this calculator removes the guesswork from your plant care routine.

How to Use

Select your plant type.
Input your environmental conditions.
Get your personalized recommendation.

The Importance of Precision

Every plant species has adapted to specific conditions in the wild. By mimicking those conditions in your home, you can dramatically increase the lifespan and vitality of your collection.

Visual Reference: Bright Indirect Light

Houseplant near window with sheer curtains

Bright Indirect Light (Diffused): This is the ideal lighting for most tropical houseplants. The light is bright enough to read a book comfortably, but the sheer curtain diffuses the harsh direct rays that would otherwise scorch the leaves.

Lux and Foot-Candle Reference Guide

Light Category	Lux Range	Foot-Candles (FC)	Best For
Full Sun / Direct	10,000+	1,000+	Cacti, succulents, fruit trees
Bright Indirect	2,000 - 10,000	200 - 1,000	Monstera, Ficus, Aroids
Medium Light	500 - 2,000	50 - 200	Pothos, Philodendron, Aglaonema
Low Light	< 500	< 50	ZZ Plant, Snake Plant (minimal growth)

Note: 1 foot-candle ≈ 10.764 lux. Use a dedicated light meter or a smartphone app at plant height during midday for accurate readings.

Recommended next actions

Use the result in a real care workflow with plant profiles, guides, and personalized quizzes.

Topic Guide

Bright Indirect Light

Learn everything about bright indirect light for your indoor and aquarium plants. Expert care tips, troubleshooting, and related guides.

Topic Guide

Direct Sunlight

Learn everything about direct sunlight for your indoor and aquarium plants. Expert care tips, troubleshooting, and related guides.

Topic Guide

Low Light

Learn everything about low light for your indoor and aquarium plants. Expert care tips, troubleshooting, and related guides.

Topic Guide

Grow Lights

Learn everything about grow lights for your indoor and aquarium plants. Expert care tips, troubleshooting, and related guides.

Topic Guide

Sunburn

Learn everything about sunburn for your indoor and aquarium plants. Expert care tips, troubleshooting, and related guides.

Sunlight Calculator Variations & Requirements

Variation	Light Requirement	Watering Frequency	Difficulty
Standard	Bright Indirect	Weekly	Medium
Variegated	High Light	Weekly	Hard
Dwarf	Medium Light	Bi-Weekly	Easy

Troubleshooting & Diagnostics Guide

1 Plant is dropping leaves despite following the recommendation

Diagnosis: Drafts, sudden temperature changes, or pest issues not related to the calculator's focus area.

Treatment: Isolate the plant, check for pests, and ensure it is away from heating/cooling vents.

Glossary of Terms

Transpiration: The process of water movement through a plant and its evaporation from aerial parts.
Photoperiod: The period of time each day during which an organism receives illumination.

Frequently Asked Questions

Does this calculator work for both indoor and outdoor balconies?

Yes — by selecting 'Outdoor open sky' or adjusting the obstruction level, the calculator modifies its lighting metrics. It perfectly bridges the gap between indoor window sill lighting and partially exposed outdoor environments.

What if I don't know which direction my window faces?

You can use the compass app on your smartphone. Stand facing the window and check the direction. Even an approximate direction (like 'mostly South') will yield highly accurate light level estimates.

What does 'Bright Indirect' light actually mean?

Bright indirect light means the plant is in a very bright room, often right next to an East or West window, but the sun's direct rays do not physically touch the leaves. It is the optimal lighting condition for 90% of tropical houseplants.

Why does distance from the window matter so much?

Light intensity drops exponentially, not linearly, as you move away from a window (the inverse square law). A plant placed just 2 meters away from a South-facing window receives less than 20% of the light it would get right on the sill.

How do sheer curtains affect light levels?

Sheer curtains filter out harsh UV rays and diffuse the light, turning dangerous 'Direct Sun' into safe 'Bright Indirect' light. If you have a South-facing window, adding a sheer curtain is the easiest way to protect sensitive foliage.

Why is my plant stretching and looking leggy?

This is called etiolation. Your plant is not receiving enough light and is desperately stretching toward the nearest light source to survive. You must move the plant closer to the window or invest in a grow light.

Why do my plant's leaves look bleached or washed out?

Bleached, yellowing, or transparent leaves usually indicate extreme light stress. The plant is receiving too much direct sun, which destroys the chlorophyll. Move the plant a meter back from the window or add a sheer curtain.

How do seasonal changes affect my window's light?

In the Northern Hemisphere, the sun sits much lower in the sky during winter, drastically changing the angle of light entering South windows. You should re-run this calculator at the solstices to see if your plants need relocation.

Scientific References

Light and Plant Growth — Royal Horticultural Society

Source: rhs.org.uk
Effects of Light Intensity on Houseplant Growth — NC State Extension

Source: content.ces.ncsu.edu

Reader Feedback

Feedback from PlantSolve readers who have used this guide. (2 reviews)

Elena R.

Madrid, ES

Estimated light levels by window exposure

Helped me understand the light exposure from my south-facing window direction, so I knew whether to supplement with grow lights.

Trevor H.

Boston, MA

Compared direct vs indirect exposure levels

Helped me compare the light levels near my south-facing window to keep conditions in the bright indirect range for my houseplants.

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