Iris – How to Grow


How To Grow Tall Bearded Iris

viette gardens iris exotic starSoil Requirements

Requires well-drained soil. Take care not to over water as they won’t tolerate “wet feet”.

Sun Requirements

Plant in full sun or at least all afternoon sun.


Plant any time, but they do best when planted July through September as bare root divisions. Space 12 - 18 inches apart and set top of rhizome at soil surface. Do not mulch.


Do not use a high nitrogen fertilizer. We recommend Plant-tone, rock phosphate, and green sand when planting. Iris are heavy feeders and require regular fertilization with Plant-tone.


Divide every 5 - 7 years any time from June to October. Cut the leaves back to 6 inches when dividing.

viette gardens iris greenan castlePest & Disease - Iris Borer and Leaf Spot

Spray Schedule: March 1, April 1, April 15, May 1.

Spray (use according to label directions): Sevin, Bonide Eight, Bt (Bacillus thuringiensis), or Bug-B-Gon

Winter Protection

In the fall, cut the foliage back and destroy it. This prevents pests from wintering in your iris foliage. Winter mulch is usually not needed.

When Iris Don't Bloom

The possible reasons for Iris not blooming include a non-hardy variety (flower buds freeze), over-fertilization with a high nitrogen fertilizer, over-watering or poor drainage.