Iris Plants Do Not Bloom Anymore

Question From: Waters, Michigan, United States
Q: My iris plants are 3 years old, purchased from an iris farm in northern Michigan. I live in Gaylord, MI. The first spring after planting they were beautiful...nice big flowers. The past 2 springs I have not had ONE flower. I followed the directions from the farm and used triple super phosphate fertilizer as directed. HELP!!! What can I do?

A: Look to see if the rhizomes have been damage either by borers or disease. If so remove the damaged ones. If they were planted too close together, they may need dividing. Are they getting good sun? They need six hours a day. I have some planted in sandy soil and they are thriving. I do not fertilize them. I have some planted in a raised bed of clay based soil- they bloom every year. I do not fertilize them. I'd lay off the fertilizer. Also, do not cover the rhizomes with mulch. If they are buried too deep they will not bloom. The tops of rhizomes should be exposed. If you mulch them in winter remove it in spring. Hope you have a good show next year. Best Nancy