REBLOOMING IRISES are simply irises that have an extra gene in their DNA that triggers a second bloom period later in the year. It is to be understood that rebloom is not a perfect science. We can only state that with proper care the reblooming irises we sell, can and do rebloom with some regularity. The keys to rebloom are water through the summer months and fertilization on a regular basis. It should be understood that even with these things, sometimes reblooming irises just don't rebloom. With this in mind, we do not guarantee rebloom. It is worth the extra effort and these irises are always among our top sellers each year. Please note, we have tried to list the best irises for colder climates.