Internode
/ˈɪntɚˌnoʊd/
Definition
Internode refers to the section of a plant stem between two nodes, the points where leaves, buds, or branches attach. It is a stem structure, not a separate organ. Internodes lengthen as shoots grow, helping space leaves and branches along the stem. Their length varies by species, light, and growing conditions, and it affects a plant’s overall shape, from compact growth to long, stretched stems.
Function in Plants
- Stem spacing and light capture: Its length sets the distance between leaves and buds, which shapes how a plant spreads foliage and reaches light. Longer sections can open the canopy, while shorter ones make growth look more compact.
- Response to environment and hormones: Elongation is influenced by light quality, day length, temperature, and plant hormones such as gibberellins, which help drive stem extension. Low light often leads to longer, weaker growth.
- Clue for plant identification: Botanists and growers often compare length, thickness, and surface features when describing species or cultivars. These traits can help separate similar plants during identification.
- Use in pruning and propagation: Buds occur at nodes, not along the internode, so cut placement matters when pruning or taking stem cuttings. A section that is too long can make plants look leggy and less sturdy.
Related Terms
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Meristem
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