Etiolation
Etiolation is the process in which plants grow long, pale and unhealthy due to the lack of light. Etiolated plants are susceptible to disease and may die quickly due to a lack of energy.
The word etiolate is thought to have come from the French word “étioler” that referenced depriving celery of light. Plants that are grown in the absence of light or not enough light become pale, have unexpanded leaves, and long weak shoots. The pale appearance is the result of a lack of chlorophyll, the pigment that supports photosynthesis, the primary source of energy in plants.
Symptoms
Plants will have long and weak stems that may require staking.
Leaves will have a pale yellow colour, and may not unfurl properly.
Treatment
Knowing how to choose your plant to fit your environment is the best way to prevent etiolation. The next best way is to move your plant somewhere with more sunlight!
If you cannot move your plant, you will need to change things in its environment to allow it to get more light. Thinning and pruning nearby plants will reduce shade, and purchasing grow lights may be a stopgap measure worth considering.