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Nodes
A node is an area on a stem where buds are located (Figure 6). It is a site of great cellular activity and growth, where small buds develop into leaves, stems, or flowers. When pruning, it is important to locate a plant's nodes. Generally, you want to make a pruning cut just above, but not too close to, a node. Pruning in this manner encourages the buds at that node to begin development and ultimately form new stems or leaves.
The area between two nodes is called an internode. Its length depends on many factors, including genetics. Several other factors also can influence internode length:
- Reduced soil fertility decreases internode length, while an application of high-nitrogen fertilizer can greatly increase it.
- Lack of light increases internode length and causes a spindly stem. This situation is known as stretch, or etiolation, and often occurs in seedlings started indoors and in house plants that do not get enough sunlight.
- Internode length also varies with the season. Early-season growth has long internodes, while late-season growth generally has much shorter internodes.
- If a stem's energy is divided among three or four side stems, or is diverted into fruit growth and development, internode length is shortened.
- Plant growth regulator substances and herbicides also can influence internode length.
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