Reblooming or remontant iris are varieties that produce more than one crop of bloom stalks in a single growing season. In northern areas this generally means a "fall bloom". In other areas it may be a 2nd bloom time during summer.
Rebloomers are found in bearded iris and beardless iris as well! Beardless varieties are generally called, "repeaters" instead of rebloomers.
Please check our list of rebloomers according to zone (click on your zone below the main "rebloomer" category to find out if the iris you are interested in has been known to rebloom in your zone!
Why do rebloomers send up another bloom cycle? Genetically, rebloomers have not one but several sets of genes that determine the frequency and quality of a rebloom. All rebloomers contain signals in their make up to not require a prolonged vernalization period (cold temp) in order to induce bloom.
While the second bloom is not guaranteed, some iris growers love the potential for a second bloom.