In nature, plants will stretch to receive as much light as possible. This stretching is called etiolation. Characteristics of etiolation include long, leggy growth and weak stems. The stems and leaves are often pale in color, typically white or yellow. The pale color is caused by a lack of chlorophyll – the pigment in leaves that makes them green. Internodes (the length between growing points on a stem) are longer and leaves are sparse.
The plant stretches during etiolation because it increases the likelihood of it finding light. Indoor plants will often do this when they are in very low light. In some cases, the stretching will help the plant find light from a nearby window or light.
When plants are grouped together tightly, become overgrown or placed in low light, they will etiolate. Etiolation should be avoided with indoor plants as best as possible because the resulting plant growth is weak, leggy and unattractive.
The best ways to overcome etiolation are to select sites with proper light, space plants appropriately, and keep plants pruned properly to allow light to penetrate all plant surfaces as best as possible.
Green Side Up,
Senior Horticulturalist, Matt Kostelnick
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