How to Fertilize Iris 'Dutch'?
Diluted iris feed every three to four weeks during spring bloom

Iris 'Dutch' · Iris 'Dutch'
Grow in well-drained, fertile, neutral to slightly acid soil in full sun. Good for naturalising - choose a location where the soil will be hot and dry during the summer months. See bulb iris cultivation and bulbs: naturalising for further advice
Diluted iris feed every three to four weeks during spring bloom