How do I know if my plants get enough light?
Written by
Olivia Mitchell
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Understanding appropriate light levels prevents common problems with plant health. Healthy plants are characterized by their vibrant colors and regular, symmetrical growth patterns. When plants do not have adequate light, leggy stems develop with long distances between leaves. Variegated plants will lose their patterns and turn solid green when exposed to insufficient light. Tiny leaf development means a lack of energy for photosynthesis.
Growth Patterns
- Leggy stems stretching toward light sources
- Asymmetrical development favoring brighter areas
- Slowed or halted new leaf production
- Failure to flower in blooming species
Leaf Changes
- Loss of variegation patterns in colored foliage
- Yellowing of lower leaves due to nutrient diversion
- Smaller than normal leaf size
- Thinner leaf structure with reduced rigidity
For a true evaluation, perform the hand shadow test during midday hours. When you are under direct daylight, hold your hand about 12 inches over the plant. A strong and distinct shadow with sharp edges suggests adequate intensity. If your shadow is fuzzy and weak, the light levels are too low and need to be higher.
Based on the measurements and responses of plants, adjust light intensity. All light-sensitive plants should be touched and moved closer to windows gradually. Use full-spectrum LEDs when natural light falls below 200 μmol/m²/s, and increase the hours by 2-4 hours if plants are struggling. Take special care to rotate specimens weekly to have uniform exposure.
Distinct plants exhibit diverse recovery indicators when light is enhanced. Leafy foliage plants will create larger, darker leaves in just weeks. Flowering types develop buds when they receive the proper spectrum of light. Succulents typically exhibit compact, short growth habits. Palms will unfurl their fronds in Uterms or quicker. Record those positive benefits.
Read the full article: Indoor Plant Lighting Essentials Explained
