How to Prune plantain lily 'August Moon'?
Remove spent foliage as required and clear up dead foliage when it dies back at the end of growing season

plantain lily 'August Moon' · Hosta 'August Moon'
Grow in fertile moist but well drained soil in part shade with shelter from cold,dry winds. Grow this hosta in a sunny spot this will enhance the yellow foliage. See Hosta cultivation
Remove spent foliage as required and clear up dead foliage when it dies back at the end of growing season