Answer: Generally, Dutch irises aren't suited to growing in your area. They are native to South Africa, where they receive a period of dry weather that allows them to rest, and rest is crucial to bloom. It sounds like your iris didn't have their rest if they were able to grow all winter. Instead, try English irises and rhizomatous irises, including Japanese, Siberian, and bearded types, which are better adapted to your region (where rest should come in the form of winter chilling). You can plant them September, and look forward to blossoms the next spring. Enjoy!
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