Training & Plant Architecture

Pruning, Branch Selection & Source-Sink Balance

Pruning changes the number and position of growing sinks and the source leaves that support them. Branch selection is therefore a structural and physiological decision, not simply removal of everything below a fixed height.

Key concepts

  • Growing shoots and flowers compete for assimilates and mineral resources
  • Source leaves support multiple sinks through the phloem network
  • Pruning changes architecture and hormonal signaling as well as resource demand
  • Different branch positions can experience different light and airflow

What to measure or observe

  • Record branch number and position before pruning
  • Track shoot growth after pruning
  • Compare retained branch light exposure
  • Observe wound closure and plant recovery

Common mistakes

  • Using one pruning height on plants of different structure
  • Removing source leaves and branches without distinguishing them
  • Pruning stressed plants heavily
  • Assuming lower position alone makes a branch unproductive

Visuals this lesson still needs

  • Source-sink branch map
  • Pruning decision tree
  • Branch-position light comparison
  • Post-pruning recovery sequence