no trick, if you live in ca i think you need to divide every 2 years for maximum blooms spring and summer, they just grow to fast here and crowd out and you will get small rhizomes and blooms.

Per the link below...

Reblooming Iris
Normally all bearded Iris will bloom in the spring. There are some varieties that have a genetic tendency to bloom a second time usually in the late summer or fall. These Iris have been called "Remontant" or "Reblooming" Iris. But such rebloom is often dependent on geographic locations, climatic conditions and cultural practices. We are listing the reblooming Iris that have been the most consistent reblooming Iris for us in Oregon. But remember remontancy is NOT guaranteed.

A local grower/seller here only lists the ones that have reliably rebloomed for her as rebloomers on her price list with descriptions, which I find is quite nice.

Sue

Here is a link that might be useful: Reblooming Iris

Chere ~~ I have read it is important to give water in the summer plus another feeding.

Thank you for all the information. I just ordered some reblooming iris. I am going to lay down some small chicken wire first because a gopher did get in to my front flower bed and ate two then cover it up with some good soil I bought. I will also mix in bone mill and sprinkle with repellent for skunks and raccoons and other critters who might dig them up while looking for other things. I'll let you know if they rebloom.

Chere