How to Prune plantain lily 'Slim and Trim'?
No pruning required

plantain lily 'Slim and Trim' · Hosta 'Slim and Trim'
Grow in fertile, moist but well-drained soil that doesn't dry out, in full or partial shade. Protect from cold, drying winds, and mulch in spring to conserve moisture. See hosta cultivation for more detailed advice
No pruning required