Q.Rhododendrons, Irises Not Blooming
Strangely, both our irises and rhododendrons did not flower this year. Any suggestions?
Certified GKH Gardening Expert
Since these are two very different plants that did not bloom, I suspect that you have an issue with phosphorus in your soil. Plants need phosphorus to bloom. Here is more information on that:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm
Have your soil tested to determine what is causing the phosphorus deficiency. You can also add bone meal (https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/bone-meal-fertilizer.htm) to the soil to add phosphorus.