Grow in organically rich, medium moisture, well-drained soil in full sun to part shade. Prefers sheltered sunny locations, as near a south or west facing wall. Plant rhizomes only about 1-2" below the soil. Rhizomes tend to push out of the ground and will benefit from fall and spring mulches.
When should I divide my Japanese iris roof?
Dig and divide your plants every 3 to 4 years to maintain plant vigor. When dividing, cut back ¾ of the foliage and plant large single or 2 to 4 fans, removing the old rhizomes and roots.
How do you plant iris on a roof?
The Japanese roof iris is unique amongst irises because it grows about as well in the shade as in the sun. Like all irises, it should be planted with the rhizomes just at the surface of the soil. The colony will slowly increase in size or you can speed the process along by dividing the plants in the fall.
Where do irises grow best?
- Irises will bloom best in full sun.
- Bearded irises must not be shaded out by other plants; many do best in a special bed on their own.
- They prefer fertile, neutral to slightly acidic soil.