Technical goal. An open crown letting light reach each branch tier — flower yield rises 20–30%.

Pruning calendar by tree age

  1. Year 1–2: retain three primary branches evenly spaced.
  2. Year 3–5: develop 6–8 secondary branches at 45° angles.
  3. Year 6+: open-up cuts every 2 years.

Cut rules

  • Cut flush to the collar; leave no stub over 1 cm.
  • Slope cuts 30° downward to shed rainwater.
  • Paint diluted lime on the wound to deter fungal entry.

“Correct pruning is the cheapest investment with the longest-lasting yield effect on star anise.”
— Lào Cai Agricultural Extension Centre

Timing

30–45 days after the summer harvest, when trees have recovered but flower buds for the next season have not yet differentiated.