How to Fertilize Siberian iris 'Siobhan'?
Low nitrogen feed in spring before and after bloom

Siberian iris 'Siobhan' · Iris 'Siobhan'
Grow in any good garden soil that is preferably moist but not waterlogged. In drier soils, dig in well-rotted organic matter before planting then apply as a mulch each spring
Low nitrogen feed in spring before and after bloom