Water consistently during the growing season, keeping the soil evenly moist but not waterlogged. Reduce watering significantly in late summer and autumn as the foliage begins to yellow and die back.

Ensure good drainage to prevent bulb rot, especially during dormancy.

Remove spent flower stalks immediately after blooming to prevent seed formation, which can drain energy from the bulb.

Cut back dead or yellowing foliage to the ground in late summer or early autumn, once it has naturally withered. This helps the bulb store energy for the next year.

Iris × hollandica can be propagated by dividing overcrowded clumps in late summer or early autumn.

Carefully lift the bulbs, separate them into smaller sections ensuring each has a healthy bulb and roots, and replant them at the appropriate depth. Allow them to establish before severe frost.

Repotting is generally not a primary concern for Iris × hollandica as they are typically planted outdoors in garden beds. If grown in containers, repot every 2-3 years in late summer or early autumn to refresh the soil and divide any overcrowded bulbs, ensuring good drainage.