How to Store Iris Rhizomes
Before we look at how to keep iris over the winter, we need to make sure that it is understood that we are talking about storing iris rhizomes in this article. Irises that grow from rhizomes typically have flat, sword-shaped leaves. Proper iris rhizomes storage starts with making sure that the iris rhizomes have been properly dried. After digging them up, trim the leaves back to about 3 to 4 inches (7.5 to 10 cm.) long. Also, do not wash the dirt off. Instead, allow the iris rhizomes to sit in the sun for a day or two until the iris rhizomes are dry to the touch. Using a scrub brush, gently brush off most of the dirt. There will be some dirt left on the rhizome. The next step in preparing iris rhizomes for storage is to place them in a dark, dry, somewhat cool place to further dry or cure. They should have plenty of air ventilation and it should be about 70 F. (21 C.). Leave the iris rhizomes there for one to two weeks. After the iris rhizomes have cured, coat them in powdered sulfur or other anti-fungal powder. This will help prevent rot from setting in on the rhizomes. The last step in storing iris rhizomes is to wrap each rhizome in a piece of newspaper and place in a box. Put the box in a cool, dry place. Every few weeks, check on the iris rhizomes to make sure that rot has not set in. If the iris rhizomes start to rot, they will feel soft and mushy instead of firm. If any do start to rot, discard the rotting iris rhizomes so that the fungus does not transfer to any other rhizomes in the box.
