Soaking Rhizomes in Bleach Before Transplanting
When transplanting irises, do they need to be treated with a bleach solution?
Certified GKH Gardening Expert
You do not need to treat them with bleach. Soaking in a bleach solution is standard only if disease was previously a problem. While diseased material should always be discarded, soaking is oftentimes done to kill any remaining spores that may be on the rhizomes. If your rhizomes were affected by fungal infections in the past, then you can soak them in a solution of 1 part household bleach to 9 parts water for 30 minutes. Make sure they dry out before replanting.
I never have. Sometimes iris get wirns, as gross as that sounds, and have to be treated with an insecticide soak but if the rhyzomes look healthy, there is no need to do any pre-planting treatment.