How to Prune Simon bamboo?
Remove weak, dead, damaged or spindly stems in spring and thin to show off stems to best effect. Cut out any flowering shoots promptly to discourage more from forming - see bamboo cultivation

Simon bamboo · Pleioblastus simonii
Grow in fertile, humus-rich, moist but well-drained soil, in full sun or partial shade. Protect from cold drying winds. Creeping rootstock can become invasive in warm, moist or favourable conditions and need restraining ; see bamboo control and bamboo cultivation
Remove weak, dead, damaged or spindly stems in spring and thin to show off stems to best effect. Cut out any flowering shoots promptly to discourage more from forming - see bamboo cultivation